So yeah I would like to know if Kayle is still viable since I haven't played her in ages....
Last time I played her was before she got reworked and where she was still fun in my opinion, stopped playing her afterwards....
Also I've seen Kayle's rarely at this time so that's another point why I'm asking.

Some might say yes, and a lot will say no.

Her ult can be rage-inducing with the right team.

Besides that, other supports support better, and other carries carry harder. She can do a bit of both, but since you will most likely have a top tier carry and a top tier support in your team on any game where viability is a concern, it's kinda redundant to pick her. She's mainly a filler, to give your team an extra boost in DPS and support.

She just has too slow a start imo

Kayle's pretty underrated in the grand scheme of things. Her downside is her awful early game, but she shines later on. She can't carry as hard as actual carries, but she's a hybrid carry/support. Carries can't give 3 seconds of invincibility to a team mate on a short cooldown.

Kayle suffers from massive mana problems. She only ever gets to do anything when she has golem buff. This prevents her from farming or getting good early kills, which in turn makes her late game lackluster.