The Fifth of the Five Ways

[Deesse23]

Aquinas could have been a young earth creationist for all I care, it doesn't change how the argument itself is interpreted by modern Thomists. And it's the updated arguments/interpretations that the atheist who wishes to critique arguments for God should focus on ... after, of course, first understanding the argument properly.

What you are saying is that the original intent does not matter but modern interpretations (or shall we say "retrofits" to match modern knowledge and understanding) do? If Aquinas uses a methodology (philosophy) and comes to wrong conclusions* (young earth creationism), then it does matter very much, because then we can conclude that his method is not the very best fo rfinding out what is true. "Massaging" his original methods and results into what you want it to say today, or retrofitting it to match more recent findings, that is dishonest.

* or even worse (and matter of fact in Aquinas´case): creating a method/philosophy to match what you already believe