Also, using a pressure cooking on any slow cook meat works in a fraction of the time and is super tender.
IMO boiling takes the flavor out. Not sure about pressure cooker.
An Asian method is to boil ribs, then add the sauce on the grill.
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I’ve boiled ribs. Exactly once. Never again.
I hated pouring all that flavor down the drain.
If you cook low and slow, there is no need for parboiling.