Its easy to offer hypothetical solutions for a far when details are amis. It's another thing to deal with local politics

I have no particular objection to building datacenters there.

All that said, I think you're being real hand-wave-y here. The climate in Houston is materially different than it is in Dallas. So there's likely a reason these companies have been locating their enormously expensive assets where they have been locating them.

Houston floods. Often.

Houston gets hit by Hurricanes.

Houston is hot and humid with relatively high ground water tables.

Don't even get me started on the power and the durability issues arising from the use of sea water.

There's a lot to work out there. You put what you can afford to lose in Houston, but you don't bet the farm on coastal Texas. You just can't do that if you want resilient infrastructure.

Im not saying it can't be done, but building near the ocean has its own set of drawbacks and costs.