/e/OS-T GSI will - perhaps one day - close a gap in the GSI landscape, as it allows especially newer device generations not supported by custom ROMs to be degoogled with /e/OS, even if not everything works one hundred per cent.
By the way: I have a Xiaomi Mi A2, which will probably be removed from /e/OS-R support in a few months { “For now we will continue building A11, but probably not for so long (and without security patches)” } equipped with AOSP 14 + microG suite 3.1.x. All basic functions and apps work. So the chances of a longer life are very high.