TLDR: WiFi 7 isn't even ratified or "out" yet, so of course there isn't enough hardware for it.
The WiFi 7 standard hasn't even been finalized. It's not unusual to see companies marketing hardware BEFORE final ratification, but it's like a marketing gimmick more than an actual case of "early adoption" hardware. If you're seeing a situation like this one where a few companies sell routers that support the equipment standard, and there's only one of two adapters that do, just stay away. The Wi-Fi Alliance JUST released the WF7 certification criteria on January 8th, so maybe companies will start trying to release hardware now.