not really.
Firstly Czechia is central Europe, not eastern and is also a very progressive place as far as LGBT+ freedom and rights are concerned, especially compared to some of it's neighbours (Poland, Slovakia) so being gay isn't a big deal there. I think it's down to how religious the people are, Slovakia and Poland are very Catholic where as Czech people are more secular. I would say that compared to the USA, there's less stigma around being gay in Czechia, and European views in general on nudity and sex is very open compared to USA and UK - Even Ukranian president Zelensky's comedy career started with nudity, sex and dick jokes, so even the east isn't as uptight as you suggest.
Czechia is also one of the largest producers of pornography as far as population go, there's an article
https://www.praguemorning.cz/the-czech-republic-land-of-pleasure-eweunyi0oq/
"Despite possessing slightly over 10.5 million inhabitants (about 0.14% of the world population), the Czech Republic is the third nation in the world in the number of porn stars behind only the United States and Russia. In fact, 12.88% of the world total of adult film stars comes from Bohemia and Moravia. According to one estimate, there are 70.7 porn actors and actresses for every million inhabitants."
So pornography isn't a strange industry to get into if you're from or in Czechia. A lot of Czech male models can use pornography as a launchpad for their careers without having it affect their future career like they would in the USA.
The reason why a lot of Czech people go into porn is most likely the same as why Americans do, money. Whether it's a choice or desperation, money's money.
