Ben Torah-
Learning in Kollel is 100% a legitimate parnasa. If I become a baseball player and I have people pay to watch me play ball, that’s OK, but if I become a scholar and have people pay me to learn – that’s not?? If I got a job in a think-tank thinking of stuff all day, that’s wonderful – but if I get a job in Kollel thinking of Chidushei Torah that’s not?? Why should learning be any less?
It all depends on where the money comes from. If his parents are supporting him or if his wife is supporting him then yes it is a 100% legitimate form of income. If the money is coming from other sources, which is beyond the scope of this thread, then no, it is not a legitimate source of income.
The difference between being a baseball player and being supported by your fans and learning in Kollel and being supported by the community is that fans decide based on ones performance if they want to pay to watch you play. It’s totally their decision.