2 points left and basically the same seat leave Garcia in an OK position; it was possible for him to be given a Biden+20 seat or so. Given his 2020 performance he may do OK in Biden+12.
By contrast Issa became an underperformer by the mid-2010s and even though I generally think the GOP will be OK in Biden+6 seats I wonder if Issa specifically might not be doomed.
I think Garcia is probably doomed the cycle after the first GOP majority. It will be almost impossible for a GOP incumbent to win a Biden+12 seat if they are voting for GOP legislative initiatives. And if they aren't, well the CA GOP despite top 2 has never really adapted to moderates in either party. Which means you get constant turnout battles.
I just am not sure Biden+10 or 12 or even 8 will make a difference then. Ie. it would have in 2020, but next time 2018 rolls around he will probably end up losing by 6+ anyway.