There are dive sites out of the areas you mention, unfortuanetly they are pretty far of shore. Been to the Flower Gardens numerosu times but it is a long trip and even on big boats depends on weather. There is the idea some people have that the Gulf is like a lake. Trust me, when the weather goes bad, the Gulf is as bad as you want it to be and then some. I was a geologist and used to go out to the rigs, helicopter or boat, I have seen huge waves--HUGE.
We used to take our boat out to close in rigs with some success, one day we and two other boats ran out to Stetson Banks, a long run in small boats! There are numerous wrecks not well known sitting here and there and most people know nothing of them and those who do don't give out coordinates. I by chance once found a set of shrimp boats on a sand bottom in about 70 feet. Another time I found an old offshore service boat sitting in about 60 to 70 feet and it had not been stripped!! This was pre GPS. Other locals knew of similar stuff. Viz can run from zero to over a hundred feet---and often varies significantly within a few hours or day to day. I also found some small rocks, covered with fish! Since the bottom is mostly mud and sand for miles and miles, any structure or wreckage is covered with fish.
For the most part--the answer to your question is --NO----there is no easily accesible diving out of the Texas coast/ offshore. Big water, big distances make it a challenge. N
