As I've said elsewhere, most of Trump's gains among Latinos came not from converting previously Democratic voters, but rather from turning out people who didn't vote before. This is especially evident if you compare raw vote totals in southern FL & TX in the 2016 and 2020 elections, where Trump's 2020 raw vote totals far exceeded his 2016 raw vote totals but Biden's 2020 raw vote totals didn't change by that much from Clinton's 2016 raw vote totals. For example, in Miami-Dade County, Trump gained nearly 199K votes from 2016 to 2020, while Biden lost only about 6K votes compared to Clinton - it's clear that most of this difference came from new voters rather than converting previously Democratic voters.
True, but considering how high turnout these elections were and the fact that Biden also probably brought out some new voters yet his totals largely remained the same in a lot of these locations, there almost certainly had to be some level of conversion happening as well. The question is how much of Trump's gains among Latinos and other minorities consisted of new voters and how much consisted of converting former Democratic votes. The majority of his gains were obviously previous non-voters, but how much of a majority? 90%? 75%? 66%? 55%?
Another thing to keep in mind though is that Trump's performance with Hispanics improved the most with Protestants, he made significantly less inroads with Catholics and Unaffiliateds. Conservative Hispanic Protestants either coming out to vote for the first time or switching away from voting Democratic are, in my opinion, probably going to be part of a more long-term alignment towards the Republicans, so I wouldn't be surprised if the GOP has a higher floor than the '08-'16 elections from now on in Hispanic areas.
But at the same time, we have no idea how reliable these new voters are, or if some of them could still swing towards the Democrats under certain circumstances, so it's also possible that Republicans could go several elections cycles performing well below the 2020 numbers. Time will tell what exactly is going on.
