"Tax credits  – are worth about $100-billion a year in foregone federal revenue."

When politicians talk about "forgone revenue", they are presuming that your money and earnings actually belong to them.

By far the biggest credit is the one you get for being a person.  That credit eliminates tax on the first $11,474 you earn, and likely accounts for about $44 billion of "forgone" federal revenue.  Credits for being a senior, for having dependents, for paying EI or CPP, for being employed and for being disabled account for almost all of the rest of this supposedly "forgone revenue".

Thus "forgone revenue" in this context is a term that implies that you should be taxed on every dollar you earn, even if you are poor, disabled, aged, or have a family to feed from your meagre earnings.

The 'boutique tax credits' described in this article amount to peanut money tossed about to encourage certain desirable types of activity, kind of like creating HOV lanes for battery powered cars.