No you have not. Please don't project your personal experience onto the player base in general.
A 3 point difference means a 15 percentage point difference in making a roll or not. Perhaps you can't notice the difference, but that doesn't mean it isn't there.
Most games never make it to 10th level. The vast majority actually. Prior to that you get one, maybe two attacks a round in combat, and combat is the place where you notice the bonuses the best.
15% means 3 extra hits every 20 swings, and with one attack it will take you 4-5 fights to reach 20 swings. That's less than 1 extra hit per fight. With the randomness of the d20 roll, it's not possible to notice if your hitting well is due to random luck, or that less than 1 extra hit per fight. You just can't know. Add to that 5e's balance around bags of hit points and that extra hit doesn't do much of anything even when it happens.
And that's at +3!!! +1 and +2 are even less noticeable.
If we are talking ability checks and not combat, the very few extra successes are spread out over a much longer period of time and are even less noticeable.
And "bounded accuracy" doesn't mean numbers have lost meaning either. It means that numbers don't increase with level (as much), and it can mean some rolls get easier as you level up.
I didn't say lost meaning. I said means far less, and that's factually true. In a bounded system where you don't need to keep scraping up higher and higher bonuses like in prior editions, bonuses mean far less. Not only do you not fall behind if you don't get them, you don't even need them to do very well. I already showed a CR 10 creature with DCs of 14.
And sure, the difference in having to roll at least a 5 and succeeding even on a 2 is a 3 point difference, but a 95% success rate is only 19 percent bigger than a 80% success rate.
But when you're asked to make more difficult rolls (DC 20 and above) - saving throws in particular - you will still sorely miss that 3 point bump. If you're asked to make a DC 21 saving throw and you have a +2 modifier, you need to roll 19 on the die; a 10% chance. If you somehow got a +3 bonus suddenly you have a 25% chance.
By the time you are making those DCs saves, there are other things in play to help you make saves. And that's for the 3% of campaigns that reach level 15+ Others aren't seeing save DCs of 20+ unless the DM is not using the 5e DC system as written and intended.
Some DMs like it when even specialized characters get challenged, and offer skill check DCs even higher than that. Your DM might never challenge your characters this way, but don't assume that experience is shared by everyone.
Then the DM is misusing the DC system to do that. The overwhelming majority of DCs in the bounded 5e system, if DCs are assigned as the game intends, will be 10-15. If the DM is artificially inflating the DCs past what is appropriate just so that he can challenge the expertise rogue or bard with a high stat bonus, then the resulting problems with the other PCs are the DM's fault, not that of the 5e system.
If going by 5e RAW, bonuses don't matter much. If the DM is creating a problem where bonuses start to matter more like you suggest above, that's on the DM. I'm still not wrong with my general claim about bonuses not mattering much in 5e. I'm not talking about games with DM created problems. I'm talking about the game as written.