The part shortage will not end in the next couple of years. Period. Current delivery dates on many standard Shimano parts are reading October and November of next year. I am kinda chapped they decided to launch the new groups yesterday with OEM deliveries in October. I get it - you can't stop multi-year design, testing and manufacturing processes because of a pandemic and then sit on the new tech while it slowly gets outclassed by new tech or competitors... but... I take it as a measure of good faith if you can actually have basic chains in stock anywhere before pushing these systems on top end clients,
The over $4k retail price for the new DA group is another punch in the junk.
Seriously I can't stress this enough - if you like riding your bike then source replacement standard wear parts sooner rather than later. If you don't absolutely need it yet then don't over pay for it but if it's in stock at normal price then I suggest grabbing what you could foreseeably need in the next year or two.