Re: More experience as a drummer, less muffling of the kit..what does that tell us?
Well, sometimes I'll muffle a drum -usually in an extreme sort of circumstance, like going for an effect by draping towels over the drums, that sort of thing. Also, if you don't have a good sounding room (or experienced engineer) sometimes it's necessary to muffle drums when recording. it all depends on the situation, and type of music really.
But, yeah, in general I agree with you. I think you're right about 'aquiring the taste' for an open sound. I think the other part of it is that, with experience, you get better at tuning and learn about different head types, so you don't need muffling to get the sound you're after.