From what I've read, Bitcoin now charges high transaction fee and long transaction wait time so it can't presently be used:
a) for a conversion from Bitcoin to cash?
or b) purchases using Bitcoin?

Bitcoin from my perspective can be use for series of things, in terms of transaction, nothing Bitcoin can not purchase, what ever thing fiat can can do, cryptocurrency can do it more better,converting any crytocurrency to cash is easier now due to adoption of banking system but the aspect of fees is quite annoying that bitcoin fees is now becoming ambiguous with transaction fees, which I don't the Genesis of it's regulations with charges.