Platform pretty much DOA if you're willing to wait for next year TR/TRP release on Zen4.
Not really huge amount of difference. A bit here and there, but nobody sane will justify 50% cost increase for few seconds here and there. AMD adapted very well to being Red Intel/nVidia. 5% improvement, 50% price increase. At least they stay inside same power envelope.
I wouldn't go that far that AMD killed Threadripper (for normal folks). Right now makes 0 sense to update TRX40 line which is dead for 2 years. With upcoming release of Zen4 I think "normal" TR will come again. If not, that will be tough pill to swallow to jump into EPYC DDR5 platform with overinflated prices - assuming of course World won't be consumed by nuclear winter in next 6 months.