I had fears of mold when I remodeled my basement. Although I've never had a
spot of water, I worried that some time in future anything can change and I
might end up with issues. My solution was to build my walls 3.5 inches out
from block on all walls that were buried. Lost a little space but the air is
moving behind the wall real nice.

How do you get air moving in that 3.5 inch cavity? How do you know it
is moving "nicely"?

If you provide a way for room air to enter the cavity at the bottom
and to exit the cavity at the top then simple physics will handle the
movement for you. If the basement is not otherwise conditioned, then
a 24 hr a day (ceiling) fan would give extra insurance at little
additional cost, but I might go for a cheap wall refrigerated unit if
I lived in So. Florida.

If you have a 3" cavity between the foundation and the basement
walls, haven't you just built yourself a mold-farm? (And a lovely
space for mice, to boot?) and if you exchance air between that space
and your living area, you've accomplished nothing. And if
air-changes are enough to keep the surfaces dry and mold-free,
you're better off not covering them at all, but leaving them open
to the living area. The only way this makes sense is if you're
doing the air-exchanges through a fairly good filtration system.