I'm well versed with this world, and actually blog sometimes too. Here's some observations:

1. Lots of people use credit card points and frequent flyer miles to buy premier hotel and flight experiences. For example, you can fly from the US to Europe in business class round-trip for ~120,000 points and ~$200 in taxes/fees. Buying a business class roundtrip would cost $2000-7000, depending on which airlines and which times you fly.

2. You can earn points by flying, but the fastest way is by credit card bonuses. Recently the Chase Sapphire Reserve (CSR) had a 100K point bonus if you spent $4,000 in 3 months. You could transfer those Chase points to United and nearly have enough for round-trip business class tickets. To earn 100K United miles by flying would require you to spend $9k+ dollars on united tickets (if you're top tier elite), or fly business class between US-Asia 3 times on their partners or ~6 times in economy. It's waaay faster to use credit card sign-up bonuses to earn points.

3. There are lots of bloggers. boardingarea.com is full of them. Many cards give you referral bonuses for customers, so they just use their affiliate links. They're generally trying to push the links when they can. If you're a bigger blogger, you can get a deal with a bank to get cash per referral as opposed to the "max 5 referrals per year" deal that most people get.

4. The Points Guy (TPG) gets lambasted for using referral links that have the best referral bonuses instead of what's best for the end user. For example, the CSR above (100k/$4k spend), did not give a referral bonus. It's little brother, the Chase Sapphire Preserve (CSP), gave a 50k point bonus for $4k spend, but did give the referrer a bonus as well (10k points, or some cash depending on the deal). TPG regularly linked to the CSP even when every other blog was linking to the CSR.

5. The "golden age of travel" has transformed. In the past, frequent flyer programs were very beneficial, and cards had awesome sign-up bonuses. People would "churn" cards i.e. apply for a card every 90 days to get the sign up bonus and then never use it again. After a few years it wouldn't hurt your credit score, but you can read-up more online. reddit.com/r/churning is generally a good source.

6. Nowadays you still have big card bonuses but they tend to be more for the premium credit cards ($450+ annual fee) instead of no-fee or low-fee cards. In addition, banks are tighter about how often you can apply for those cards.

7. Airlines are much stingier with their award space. Even if a business class flight is supposed to cost 55-60k miles, you need availability from your origin and destination. The airlines can simply limit availability and render your points less useful. American is notorious for this - good luck finding business class awards from the US to anywhere. United is the best because Star Alliance has a ton of partners and usually sufficient availability. Delta has variable awards so sometimes a flight will cost 50k miles and other times it will cost 100k or even 300k miles for the same flight. A real PITA :(

8. You'll notice that I am consistently talking about business class awards. That's because economy fares have become very cheap nowadays that it's better value to just buy them. If you follow Scott's Cheap Flights, you can get notifications of fare deals. You can regularly get $300-400 flights from US-Europe or $500 US-Asia flights. These flights would cost 60-70k miles roundtrip, but with CSR you can "buy them for 1.5 cents per mile," so you can use 25K chase points to buy a $375 flight, and earn miles on that flight. Conversely business class tickets usually go for $2-4K, so using 100K miles is a way better "redemption", if that's what you're interested it. Ultimately it depends on your willingness to pay - some people stretch miles to economy as much as they can.

Hope that helps as a quick primer. Happy to answer any questions. Miles & points is an interesting world but it has gotten less rewarding. Nowadays I just see them as a nice to have but not something I'd go out of my way for.