Could be higher humidity causing some fungal infection. What has your weather been like? Hot and humid?

It's been relatively mild in the 80s and low humidity.

I live in a high-humidity place and I get that sometimes on my rosettes.. but usually on the old lower leaves that are yellow and wrinkly about to die anyway so I ignore them..

Yours seem to be happening on the healthy leaves.. so odd..

Have you tried poking them off or rubbing them off? Are the leaves soft?

What's their id?

Echeverias elegans