You realise industries built up around a workforce? It’s why you have complexes of related companies in regions because they poach each other’s workforces. They don’t just build a multi-million/billion dollar facility and hope that their workforce materialises out of thin air.
Tech companies like any high-skill field, built up around universities that produce the talent. Unless you think UT-Austin is suddenly going to stop producing students, why do you think that tech companies are going to abandon all their investment?
“Look at the demographics”
Why don’t you read the US Census inflow and outflow of populations between the states? (I don’t have the software to read it on my phone rn, but I seriously doubt it supports your argument, as far as I know low COL states are attracting everyone from high COL states. The low COL states are due to low market demand from being rural and just happen to be Republican).
If it were really true that “red states” only import “red voters”, then how come cities in “red” states become increasingly “blue” over time? Keep in mind that the majority of the population even in relatively rural states is in cities. If they were really just importing Republican voters, then one would expect the voting patterns to stay the same. Anecdotally, basically every state in the West Coast and the adjoining states have been flooded with Democratic voting Californians driven out by COL in the past several decades.