5e is twice as generous as 3.5 with ASIs where you got 1 point every four levels. This was balanced out by the entire system having a lot more ways to increase your numbers, in the case of ability scores there are a buttload of different magic items that boost them either permanently or while worn (and there’s no attunement to limit to how many items you can benefit from though similar sources don’t stack benefits). Comparably 3.5 is also more generous with feats, giving them out every three character levels (not class levels) and if you’re a fighter your entire class mechanic is literally “get a bonus feat at first level and every even numbered level.” But feats in that system are mostly either less effective than 5e counterparts (5e using compressed numbers and bonded accuracy affects this) or being grouped into chains/trees of multiple feats you need to get the best affects. An example is how any specialist archer needs Point Blank Shot as a prerequisite for the more effective ones like Rapid Shot and Precise Shot.

5e is built around the idea of bonded accuracy. In super simplified terms that miss a lot of nuance, this basically means all the numbers are smaller insteqad of tacking on literally seven different modifiers to any given roll so that a mid level character isn’t good at something unless they can consistently hit a DC 30 check. This means that that +1 bonus you get to relevant rolls from a +2 ASI makes a BIG difference by comparison. Not all 5e feats are super powerful, but you get ones with multiple effects that in 3.5 would be spread around multiple feats that must be taken separately. Additionally the lower numbers you’re using means things like lower AC on monsters so that -5 penalty from Sharpshooter or GWM is often a reasonable risk for the extra damage equal to around twice what you average on your normal damage dice. These are much more powerful effects and as such you get less of them.

“A 25 in your primary ability by level 20? Nay, this shall not be!”