Texas has a bunch of advantages for manufacturing. Lawmakers are willing to work with firms, land is inexpensive and available while at the same time having lots of available workers, taxes are less, electricity is fairly inexpensive, and there is a ton of barrier island protected coastline for shipping ports. America's manufacturing rebuild cannot and will not happen in NY or CA, it is actively happening in places like TX due to such advantages.
If only they had reliable utilities. Samsung's fab in Austin got shut down for a few weeks from ice-mageddon. Messed them up enough that they threatened to leave if Texas didn't give them something to make up for it.
Your missing another big part and that's unions are hamstrung down there. A lot of places in the Midwest offer similar advantages, ports aren't as good but you can still ship a lot on the great lakes, but they won't go there because they're afraid of unions.
Not to mention all of the slave labor from all of their incarcerated immigrants, and I'm sure the US will get a tax write off or something when they finally seceded.