AMD, historically, has taken a "we don't test enterprise features on consumer SKUs, but we don't fuse them off if you really want to qualify it or let them try it" approach to e.g. ECC on consumer chips with Zen.

So it's quite possible they were doing the same with TSME, and either made a rude marketing decision that the people using it on consumer chips would probably pay for PRO chips if they were prevented from doing so, or kept getting people attempting to RMA the chips for a feature they never said worked on them not working, or there's some systemic flaw in the consumer chip's implementation that they didn't feel like trying to qualify fixing versus just killing the not-guaranteed support.

Hard to guess without more data than just them going silent about it.