Balena started collecting telemetry without disclosing it to anyone, reportedly including information about what images you were flashing. Apart from a general distaste for unconsensual telemetry, I think people were concerned the data could be used for things like helping to de-anonymize TAILS users.

Beat Saber is on Steam and is also the best selling VR game of all time, so yeah I’d say it will work. I’d be extremely surprised if it wasn’t one of the very first games Valve worked on FEX & proton optimisation for.