Not fixed employees but sometimes under contract for either a certain sex type or as a whole for a certain time.

Nowadays the girls escalate, they start with very regular stuff, not doing anal, gangbangs etc. in the beginning but grow their fan base until the studios start to bid eg for her first "blow bang" and pay a lot more to have her not doing some sex type with another studio for a certain amount of time.

If you are not able to grow your fan base fast as a model, you will not be able to demand higher rates. There are even companies specializing in social media consulting for porn stars.

I was conflating multiple issues with a single statement - a.) it seems unfair that they are paid by item by anybody so the performers have to become producers to make a more sustainable living b.) it seems like having almost monopoly status as a large producer (there are many studios from that wikipedia article but a lot of them are owned by Mindgeek, not sure what the diff is between them all) gives Mindgeek too much control over rates/contracts c.) the way Mindgeek pirates everyone via the youtube model on some of its sites squeezes out those who try to produce their own content outside of Mindgeek (those whom are not benefiting from Mindgeek's ad revenue/customer data).