I don't know much about TX, but in CA I think some voter apathy comes from the consistent results over many consecutive elections. I think you would need to look at local turnout to see how it varies when there are hotly contested decisions, i.e. districts where a seat might flip from one party to the other.

In yesterday's election, we had two Democrat candidates vying for a US Senate seat, rather than a bipartisan contest. The candidates from other parties were already squeezed out during our new open-primary election process.

Practically speaking, we don't have direct, proportional representation in most decisions. As a result, people sometimes fall into a trap where they think their personal vote will not really matter. It feels lost in the margin. The same discrete result happens whether they vote or not. This is equally true whether their views align with or against the expected outcome.