The Republican Party of California has failed perennially to reach out the very socially and fiscally conservative Latino community in California and have left the Democrats to do so. Now, if California Latinos voted for Republicans at the same rate as Latinos do in Texas, California would not be a blue nor a purple state, but likely turn redder than Texas in a heartbeat. Whether it is out of genuine understanding and common interests, or cynical politicking, any political strategy of the Republican Party that is either explicitly or de facto exclusionary of minorities, especially Latinos, is utterly inane and deservedly doomed.
I think your analysis is wrong for several reasons.
1. A majority of Latinos in Texas typically do not vote for conservative candidates. For example, in 2018 Ted Cruz got just 25% or so of the Latino vote in Texas. Latinos in Texas are slightly less liberal than Latinos nationwide are, but they are still more liberal than white voters nationwide are in terms of their self identification and voting patterns.
2. Texas has remained red so far because Latinos there are less likely to vote. Texas is 38% Hispanic, but Latinos only make up 20% of their electorate in many elections.
3. Latinos in California are more liberal than Latinos nationwide. In California 39% of Latinos call themselves liberal, 30% moderate, and 30% conservative. They are more liberal than whites in California (which is saying something considering its California).
So even if Latinos in California voted more like Latinos in Texas, the state would still be a very blue state, just a little less blue than it is now.
Point being, that while the "white grievance" type politics prevelant with Trumpism and in many state and local Republican races is certainly costing the Republicans minority votes across the board, it's their ideology as well. Moderate Republican governors are often the most popular governors in the nation and have broad demographic appeal, but the party's base will not allow anyone that is center to center right to rise into national politics beyond just a handful of house seats. When you consider how far to the left the Democrats are moving in many areas, this is a missed opportunity for Republicans. If Republicans ran more moderate candidates like Charlie Baker, they would win in landslides and enjoy approval ratings not seen decades. Oddly enough, he consistently has the highest approval ratings of any governor in the country, and that is in liberal Massachussates - yet despite being to the right of any elected Democrate these days, Charlie Baker has his highest approval ratings among Democrats and Independents, with only 48% of Republicans there approving of the job he is doing (so the problem is largely with the base in terms of broadening Republican appeal - even in liberal Massachussates, a significant percentage of the GOP base wants Trumpism style white grievance politics).
Democrats could learn from this too. Bill Clinton and his "third way" style moderate politics resulted in him leaving office the most popular president since FDR, and that was despite the scandals.
At any rate, trying to appeal to Latinos by being more socially and fiscally conservative will only lose you more Latino votes. Most of them are not that conservative, and even if they have some socially conservative beliefs, unlike white evangelicals, it's not a big voting issue for them. If the GOP wants to win more minority votes, they need to move closer to the center. If they did, it would be all theirs as neither party has much of a presence there right now.
