The English rule on costs in the County Courts of England and Wales is codified in the Civil Procedure Rules part 44 [1] (although there's more in CPR part 36, and there's recent covering case-law. The costs rules are similar in the High Court and appellate courts: the general practice is "the costs follow the event" (i.e., the winner's costs are generally at least partly paid by the loser) so long as that does not offend justice or proportionality.

A "technically you won" judgment where the winner's costs were extremely large could offend justice or proportionality enough that there is an atypical costs order favouring the winner (e.g. the winner gets at most only a small amount of its costs paid by the loser).

Costs tend to become the elephant in the room during litigation, since they increase in dramatic steps over the various phases. This tends to pressure parties into compromising their positions and settle on costs out-of-court on some privately agreed basis, rather than risk an adverse costs order if the opposing party is slightly successful. If, for example, a defendant makes a counter-claim that offsets (say) half of the claim, or simply an offer to settle for half of the claim, and the claimant insists on going to a full trial, the claimant risks having to pay both sides' costs if the defendant is successful in the offsetting counter-claim or if the defendant is only found liable for half the claim.

Cost orders often state that costs are "to be assessed if not agreed"; if the party who will be paid costs under the order has an unreasonable accounting of its costs, there is an assessment procedure wherein the court can strike out or reduce some of the costed items. Often where a very expensive lawyer is doing a lot of work compared to the price of the lawyer (and the amount of the work) being done by the party paying the costs, the courts will tend to reduce the amount of costs payable, on proportionality grounds.

Finally, prevailing parties do not fully recover the full amount they spent on the litigation in many circumstances.

The English Rule tends to contain costs, although it does not always do so. Moreover, it has the perverse effect that meritorious cases that would establish new law rarely make it all the way through trial and appeal, because when a party feels its position is less than fully solid and is seeing costs mount on both sides, it will generally try very hard to settle. A party that rejects these attempts to settle is also at risks with respect to orders on costs, so will generally accept. As a result, there is no final judgment, and the law remains unchanged no matter what the parties agree in their settlement; these cases aren't even generally reported. Unfortunately the legislature is not very quick to tidy up areas of private law where this is most common (the English law of real property is the most extreme case of this) and many cases that would help resolve oddities in the law simply never go far enough before the courts before settlement, so the oddities remain.

Additionally, under the English rule, withdrawing from a case because one does not have the money or energy to continue it to its conclusion generally has costs consequences for the withdrawing party: they pay the costs of the remaining party more or less as if they had lost. An extremely deep-pocketed party facing a party with shaky finances (even if the latter has a decent case) is often tempted to rack up significant costs and use the threat of an adverse costs order to "force" a withdrawal from the case early on. So the English rule is not really a cure-all, unless the smaller party is able to convince a judge to make an order that goes to the heart of proportionality, and that is extremely unlikely in the early phases of litigation. (On the other hand, many judges are getting fed up with the amount of costs racked up by parties during the disclosure phase, and there is recent case law that is likely to rein in this sort of abusive behaviour by deep-pocketed parties, even when they face-off against other deep-pocketed parties.)

Generally, giving discretion to courts to award parties costs (or not) based on principles like justice, proportionality, and (un)professional behaviour during the litigation, is seen as a decent step towards resolving some of the access-to-justice problems that strongly advantage the most well-funded parties at the costs of everyone else. Judges are often sensitive to public policy around access-to-justice and fairness of the justice system as a whole, but some systems tie their hands in these matters more than others.

Lastly, public funding (and some forms of quasi-public or private speculative funding) of parties who cannot afford litigation with a much larger party is fully in the realm of politics. Changes in government often lead to substantial changes in the resources available to such parties, and there is very little a party can do if it cannot afford to carry its claim or its defence to conclusion in a litigation. Conversely, making it very easy for small parties to bring non-meritorious claims against large parties just because of the apparent size-difference in the parties is also unfair: nobody should ever be able to succeed in pursuing an unjust claim. Preventing governments from tilting the playing field in various directions requires political will which is rarely there, however.

Finally, there's a diversity of opinions on how to deal with the costs of litigation (or even if there is a problem that needs to be dealt with at all) within the legal profession itself. With consensus being fleeting and rare, the lack of political will for governments and legislatures to make changes in how costs are dealt with is somewhat understandable. These differences of opinion are not all motivated by professional self-interest, either. Perverse outcomes (that are bad for the reputation of the system of justice as a whole) are a risk from any sweeping change to the current system. :-(

[1] https://www.justice.gov.uk/courts/procedure-rules/civil/rule...