As I've built two bikes since the pandemic started, can say I have not seen what you are asking anywhere. Combination of buying a complete bike being more economical with parts shortages and supply chain woes likely means it would be very difficult to find a one stop shop with everything in a single purchasable SKU. Infinite wheel & tire combinations, stem length and handlebar width make the variables even more ugly.
Best I have seen so far are vendors on ebay (and classifieds sections in certain popular riding sites) that have piecemealed entire drivetrain components - often without rotors.
I don't imagine normal bike retailers doing this because it simply isn't cost effective. From what I have seen SRAM/Shimano doesn't push bundles through sales/distribution channels, so it would be entirely up to the shop to put all of it together and market it. Most of the large online retailers will let you do a frame + full custom build and often have guided forms to help you with the component selection. If you have a frame already you're sort of on your own.
It's pretty easy to find complete sram groupsets in any configuration on Ebay. Just add a set of wheels with a sram compatible freehub and you're done. I have built many bikes with all hand selected components from Ebay. I prefer it that way over what the manufacturers offer.
