There isn't always firmware updates or on a regular schedule, particularly with network gear. The last ASUS router I had only ever had one firmware update in a few years. Ive since moved on to something more reliable, everything I run is enterprise Netgear. AI mesh always sucks because you are going wireless to wireless. While your signal strength to an extender may be good you lose half with the comms going back and forth between the router and extender and if the signal there isnt the best you lose even more. I instead have most things that dont move on a 10GBe wired lan and on the second floor I have an access point that's wired instead of using a range extender. Works far better and simply using the same SSID on both theres no disconnecting from moving around, passes off from one to the other. The difference in throughput is astounding compared to an extender. The two managed switches havent had firmware updates ever and the Nighhawk router has had one in the last two years.
