I'm hoping Samsung would be pushed to top this when they're releasing the S24 series and some of the older devices will also get upgraded to a longer software upgrade period. I just upgraded to a Fold5 after using Asus ROG Phone II for four years and messing with custom ROMs (the ROG Phone II just have one year of OS updates) just to stay up to date in regards to security and software updates is not as fun as it was a dozen years ago.
Smartphones have reached a point where it's more like a PC, where the limiting factor for the phones to get a software update is pretty much arbitrary based on the manufacturer's decision. If the ROG Phone II is still supported today, I'll be definitely still using that phone.
This 7 year update promise makes me think that Google are planning to do further modularization of Android to make it similar to desktop OS where the driver is not as tightly coupled to the OS build installed. As one of the main issues when you're trying to update an Android phone OS is the SoC manufacturer not providing any updates for it so you're SOL if you want to update your Android smartphone OS.
Apple enjoys a vertical integration for their devices to help them keep updating their devices for 5 or more years.