It's not "if" but "when" everything will be 13 gear. I wouldn't put my money on it happening in 2023 though. The move from 2x to 1x for road is far less likely to be universally adopted like it was in the MTB world. Shifting front rings while riding technical singletrack was always a pita, but on a road bike it's not really a big deal at all. I would probably be first in line for a 1x13 road setup and have been seriously considering it already with Ekar. But I think the road market will be split between 2x and 1x for at least the next 5 years, with 1x gradually gaining more popularity. There's a lot to like in getting rid of the front mech and 13 gears is enough for most use cases. It was a huge step forward for MTB drivetrains and I have never missed 2x or 3x on those for even 1 second.

So they can bring it on as far as I'm concerned. My gut feeling is 2024 for SRAM 1x13. Can't see Shimano going there until at least 2025 though.