Reports coming in from ResetEra suggest that Nintendo’s latest update for the GameCube app as part of the Nintendo Classic range has seen input lag reduced. Some games were more noticeable than others and several users reported that they had experienced input lag when playing the classic F-Zero GX video game. Several users have chimed in stating that they had also noticed a reduction in input lag, so it seems that Nintendo is committed to fixing issues found within the Nintendo Classics range which Nintendo Switch Online subscribers have access to.
Nintendo seems to have fixed input lag on GameCube Nintendo Classics app

Nice!
Yeah, I had a feeling that the latency got better after WarioWorld got added but wasn’t sure.
Good to see, this now makes it my preferred way to play GC portable since Dolphin for Android seems to keep constantly breaking.
Let me tell you from experience- F-Zero GX is NOT a game you want having input lag issues. When I first started playing it on NSO I immediately noticed something just felt off, and, yeah, there was a touch of input lag (well, there were technically two things that were off, the other being steering sensitivity, but a little tuning in the options mostly fixed that).
I haven’t touched GX on NSO since September so maybe I’ll have another go at it and see if the input lag issue is indeed improved.