Does the mempoolrbf config switch share the same default value as in 24.0?
Shouldn't it also have a "How to upgrade" for Linux OS?? I don't know why only Windows users are worth of the "How to"....

Miss this part?
or just copy over /Applications/Bitcoin-Qt (on macOS)
or bitcoind/bitcoin-qt (on Linux).
I think many linux users also use package managers which will handle this automatically.
Personally I just upgrade by coping the tarball extraction over /usr/local. It's always been a hassle-free experience. Although, I don't see Bitcoin Core in the Ubuntu repositories. (I am not sure about Debian or Arch though.)