Sound insulation - differences in interior doors?

What is a heat pump in a heat pump dryer then, if there is no compressor?

That is to say that the ventilation does not create a vacuum and air infiltration happens anyway in some way. If not, the ventilation is simply less effective. Or am I wrong?

Without appropriate overcurrent openings, the system does not function correctly - or at least not effectively.

This has nothing to do with a vacuum, but with an even air exchange.

It's not in the inventor's interest that it doesn't work well, right?

Laundry does not wash 24/7, but rather about 2 hours a day, and if the system (the air exchange) works suboptimally during that time, the effects should be limited.

Oh, I see, yes, but you want other doors to be closed too, right? You don't do that just because of the washing machine.

And when the dryer is running, the system should work well too

I am currently facing a decision regarding interior doors. Now, in addition to the normal interior doors, so-called residential entrance doors are also offered as interior doors. Does it make sense to use these in the bedroom, children's rooms, and study instead of the conventional ones? We have a very open house with a gallery, and maybe this can help reduce noise a little?

Standard doors would then be made of hollow chipboard filling (no core), and the residential entrance doors with soundproof filling and 40mm leaf thickness (37dB Rw,p) as well as a lowering bottom seal.

What do you think? Sensible or over the top?