Is there much demand? It's uncommon to witness a roadie running a 1x transmission, or expressing interest in losing a chainring.
Front shifting on Shimano's road groupsets is pretty good. Many roadies are picky about tight gear spacing, and with a 1x setup you can either choose to have poor spacing, or be stuck with an overall range size comparable to a lot of vintage 2x setups, which IMO feels kind of limiting (I like my '83 Miyata 710, but if it was my only road bike, I'd be very hesitant to do road rides in the mountains).
Heck, even with a fairly tightly-spaced cassette, you're left with a prominent weird 1-tooth to 2-tooth transition in the middle of the range. On my modern 2x, I sometimes double-shift to find a staggered ratio to smooth this out. You can't do that on a 1x, and the only "solution" would be to start with a bigger small cog and begin with 2x jumps, which would require that all of your cogs and your chainring be enormous in order to achieve similar top-of-range step sizes.