>>terafl+(OP)
Hi everyone - I'm the head of product here at Triplebyte. We did not make any intentional change to how profile visibility functions and (to the best of my knowledge) the issue referred to in OP's support response (and mentioned in the second half of OP's post) was fixed last year. (See my comment at the top of OP's link [4] for more from then.)
We'll have a more complete answer shortly.
EDIT: This does not appear to be a widespread issue. Continuing to investigate.
EDIT2: Full response from Ammon, our CEO, at https://news.ycombinator.com/item?id=31771836