I think you're misunderstanding the situation; If BEAST were to remove class limits, it has a high possibility it won't work, the tournament will become unplayable and could potentially ruin the beast's name. Why is the beast's name important? Because it's one of the few large-scale skirmish tournament in Bannerlord. If removing the class limits doesn't work, you're harming the competitive community, you're unable to switch half-way through if it's not working because teams have been getting used to the no class limits so it would ruin team composition. It would be silly to make that sacrifice, especially considering this is how the community has been playing it for a long time and would be against what people actually want, If I were a BEAST administrator (which I'm quite clearly not), I'd have declined it in a heartbeat, I'm not risking the already small competitive community for the sake of some testing. There's numerous ways this data can be collected, using the best BL tournament series just ain't it boss.
It's not about 'IF YOU DONT LIKE IT DON'T PLAY IT', especially considering you'd be removing the biggest competition (DM) and considering it's already a small competitive community which are most likely against remove class limits, do you want the best tournament series to drop from 50 teams to 20? All for the sake of some balance testing? I bloody wouldn't like that
Another important factor is that if BEAST decline having no class limits, AVRC said they were planning on making a tournament themselves; surely that's a win win? It's great that TW gave BEAST that opportunity, but it was an awful decision having these cards on the table knowing it could be extremely detrimental to the community. Not only would you have an extra tournament if AVRC made his own, you'll have one that's actually enjoyable with class limits and the other used for testing skirmish.