I too have offered suggestions and not received any feedback. It might be a case that Medium gets lots of suggestions and cannot deal with them all, which would include proper evaluation.

An analogy would be the Democrat Party. There is certainly lots of advice for how it screwed up earlier this month, much of it conflicting. But the people who will carve the next direction are those people high in the party--and they already have their own ideas.

It would be impractical for Medium to deal with all the suggestions.

I have subscribed to several "political organizations" about making a better democracy. Sometimes I reply to their emails with an invitation to inspect my ideas. So far, no response.