does irelia fall off late game?

She does fall off a litte, as she doesn't have the crazy late-game feel like Jax does.

That being said, she's generally useful to the very end of the match.

She falls off when everyone is hitting 6 items, and she can't burst down the ADC anymore, especially if the ADC has a lot of peel. But the game rarely goes that long.

Depends on what "falling off" means.

Honestly, I don't think so. Throw your ult into teamfights, use E to stun troublemakers, delete the squishies. You can dive and catch out squishies, like other bruisers can.

if you only go triforce the adc will kind of deal with you at 6 items. she is godo late game but she cant just jump and insta killl squssies as she cana t leve 9-11 with triforce. if you play full ad irelia mid like do some times then she dose not fall of. most champs that stop build damage fall off

Depends. Irelia is dependent on how well she is allowed to farm. She is just as reliant on gold(perhaps more-so) as carries are.

If she is shut down early she falls off quick. If she is allowed to get gold she will be deadly late game...but not like some others.

How is irelia splitpushing?

"Falling off late game" is just an excuse for people who start throwing lategame For example, people think Karma is bad lategame because of her "lack of a true ult", but really just pop an Ult-Q and one shot the squishies. So no, she doesn't. If you do decently you should be fine.

she actually has a quite good lategame compared to most other bruisers, as it's quite hard to peel vs her in teamfights while she can 1v1 almost anyone in a splitpush.

Melees without aoe-cc always fall of in the late, as nothing but cc and burst can save you from the massive dps of an lategame ad-carry that has support from his team.