I think more abilities should grant True Sight, like all of Lux's abilities for example. But i don't think basic abilities that reveal area's should reveal invisible champions.
The reason why is because it's not fair to the user of the stealth to have an entire mechanic of their shut down by a simple button press. Stealth champions usually take a lot of effort to use their stealth and sacrifice a lot in order to keep it, Evelynn has 0 engage and 1 disengage and she's an assassin, assassin run rampant with like 3 dashes/blinks each but because she has perma stealth, she can't have those things. Twitch and current Kha'Zix(who is getting nerfed for this) are the only exceptions that i see where they don't sacrifice anything for it. Leblanc and Talon legit have 1 second of stealth, Shaco has 1 engage and 1 disengage, and its on his Stealth ability, meaning he has to make the active choice to use it for one or the other and that's what makes it fair to me.
Like, i understand there aren't enough abilities that reveal them but AOE reveals shouldn't reveal them, i think you should have to actively try to reveal them with say a Lux E.
TLDR: You should have to pay a Reasonable Price when trying to shut down a champions entire kit, Control Wards are barely reasonable because they cover the "Active Decision" part of trying to counter Stealth, you need to actually make the decision to buy the Control Ward, knowing an evelynn is on the enemy team and i think that's much better than trying to give people more inherent power in their kits.