Whether it's damage, utility, or something else. A lot of champs, especially AP or tanks, do nothing with their autos. Ekko and Tahm having stack mechanics and extra damage on their autos isn't a bad thing, maybe the numbers aren't right but at least it feels good to auto-attack.
I think this should be a priority as Riot does their update passes
Kamai2 votes
and 
, for example, I think would as a whole kit feel worse if they had a significant reason to auto-attack. I'd have to be curious what it is specifically about auto-attacking that makes the game feel richer.
Penta Penguin1 votesThey could do something like Leona who buffs their teams autos instead of their own
Ralanr1 votesI feel that would make things more convoluted than they need to be.
Penta Penguin1 votesWell look at Vel'koz. Doesn't do a LOT but makes things a little more interesting than "I do a bit of damage that falls off infinitely after 10 minutes"
Environmentalist1 votesEvery champs auto attacks are relevant. They're all used to farm. There's a reason some champs auto's aren't AS useful, because their kit revolves around abilities. I think it's fine how it is right meow.
IcyPepper1 votesA lot of champs, especially AP
That's because those are burst :V
Autoattacks late-game are either for sustained damage, a little bit of poke, or sheen procs. Not every champion needs to have relevant autoattacks if they're unwilling to invest in it. If you buy AP items for burst, you burst but don't get much out of your autos. Want to auto more with AP scaling? Get Nashor's tooth. Want to poke with autos? Lichbane. Want some utility with your autos? Grab Iceborn Gauntlet.
You have options, but just like some champions can't burst with their abilities or some champions are melee instead of ranged, not every champion should have stronger autoattacks built into their kit. If you want it, you can buy it.