Gerrymandering does not affect whole-state races like the Senate. Nobody is re-drawing state borders for every election.

And in some areas gerrymandering did backfire as far as I read, though I didn't look at the specifics.

Gerrymandering in the south made blacks and other minorities angry and motivated them to show up. There is even a term for it in this that was recently coined by some pundits, "blacklash".

So gerrymandering very much contributed to this GOP wipeout.

Gerrymandering doesn't directly impact Senate races because they are state-wide (everyone in the whole state votes for their senators, it isn't district by district), but the Republican gerrymandering in general either backfired or had no real impact more than it helped them this cycle.

A lot of the Republican gerrymandered House districts assumed Latinos who voted for Trump quite a bit in 2024 would continue to do so, but seemingly they did not.

It was worse than doing nothing, not that worse is bad in this case. Once the intended effect of gerrymandering was overwhelmed, it created more Democratic districts than it destroyed.