Why do we use the doublespeak terms for bitcoin?
There is no "self custody" or "custodial/non custodial" Bitcoin. Either you own bitcoin or you dont't. It is that simple.
If you do not control the keys you have an IOU:
ETFs: you own a promise
Coinbase/Binance: you own a promise
Some other regulated institution/agency: you own a promise
"Custodial wallet/service": you own a promise
There is no such thing as owning bitcoin on an exchange or an ETF.
Do not forget: Bitcoin is anti-fragile and grows the most after it has been attacked
For example: After years of no real progress in L2 work (apart from lnd) there was a boom of new proposals(fedimint, cashu, Ark, mercury layer) and discussions for improvements (covenants, payment pools). This boom came only after there was real felt pain when the fees were high and the mempool did not clear anymore, because of the "NFT on bitcoin" shenanigans.
Now imagine what technologies will sprout after the shut down of the centralized coinjoin coordinators.
Usable joinmarket, more payjoin adoption? Maybe Tor only Lightning nodes and chaumian ecash mints? Or something completely new.