This is why Yasuo can never be balanced

Yasuo has long had the issue of being hard to balance and being broken in that he is really durable for a carry, but the thing is he has 2 loaded abilities in his kit.

Wind Wall RANGE: 400 COOLDOWN: 26 / 24 / 22 / 20 / 18 Wind Wall ACTIVE: Yasuo creates a gust of wind that travels forward to form a wall 400 units away from himself. The wall slowly drifts forward over 3.75 seconds, blocking all enemy projectiles (including Baron, Dragon, jungle creeps, and minions) with the exception of tower hits. WALL WIDTH: 300 / 350 / 400 / 450 / 500

This is okay. Gives a melee carry a survivability point with clear weaknesses. It may be loaded but you can deal with it.

Last Breath RANGE: 1200 COOLDOWN: 80 / 55 / 30 Last Breath ACTIVE: Yasuo blinks to the nearest visible Airborne enemy champion to the cursor, instantly generating maximum Flow. Upon arriving, he suspends all airborne units within a 400-radius of his target in the air for 1 second. PHYSICAL DAMAGE: 200 / 300 / 400 (+ 150% bonus AD) Once he lands, Yasuo deals physical damage to all nearby units and gains 50% penetration to bonus armor for 15 seconds (this affects armor from items, buffs, runes and masteries).

This is where the problem is. It's a high damage gapcloser with a huge armor pen value that has 0 counter play as it counters anything you could build to stop it and the only solution is to not get hit by one of the many CCs in the game. On top of it it does 400 damage with huge scaling late game as well as giving him even more survivability in an already no cost kit on low CD.

What nerfs needs to happen before Yasuo can ever receive buffs to make him less toxic towards non-assassins.

1. ult CD needs to be increased, 30s is way too insane for a CD on something with that much utility. Move it up to 45s to make him actually have to choose his ults, without hurting him too bad. (50% uptime on that buff is way too powerful, especially when he normally builds a ton of damage and even armor pen too)
2. Reduce armor pen to 35% on ult to allow actual counter play other than not getting hit by it and him after he already is in your face. He shouldn't obliterate a tank while they can't even fight back. Killing them under 3s with 4k hp and 200 armor when it is a 15s buff.
3. Make it give 100% -> 50/75/100% flow shield on cast to emphasize his early game squishiness.
4. Make his ult not benefit from itself on the armor pen (why does it even do this in the first place...)

What this does. Gives room for counter play to Yasuo and allows him to get his abilities balanced rather than ignoring the loaded abilities in his kit. #3 really just is to emphasize his weak early game.

I have nothing against Yasuo as a champion. He just is frustrating to play against (it's a kill him or he becomes a monster games if he picked him right) and somehow became very binary when he could be very complex. These nerfs would allow people to at least be okay with the amount of times he can use his ult. And may even open up his Q and E for adjustments and even his passive.