Did Lee Sin *really* need a buff?

no.

at least not before they removed his ability to get his passive and energy return from casting his abilities instead of actually hitting them. and also not before they add the 75% cooldown split mark/dash got. he should have like 20 seconds base cooldown on his q reduced to 5 seconds when he follows. so he cant just spam and miss it and have it available a couple of seconds later without punishment, because he can hit a minion to get his energy back. its retarded how you can dodge his shit and it makes practically no difference.

he needs to get punished harder for making mistakes before they buff him anywhere.

Kinda. Probably needed to cement his role of being a high-pressure early-game jungler more, and help with his potential to snowball allies.

The energy change was really a quality of life buff that people should be really happy for since it makes his kit a lot more fluid and doesn't really affect his kit in any way.

The ult buff however was just so he isn't so reliant on "insecing" someone late game or hes useless, gives him a reason to ult a tank and give him damage where he is lacking late game.

Yeah, he did. Flashy plays aren't enough to make him a good pick.