Have there been any changes in this regard with the time of Bitcoin Core 0.16? Then it was done well and all OK nodes accepted the second transaction with a higher Commission first, and the old one was forgotten later and discarded
No... RBF was rolled into Bitcoin Core in v0.12... which was released in February 2016. That's a full 2 years BEFORE v0.16 (Feb 2018.
The thing is that RBF was, and still is, Opt-In. You have to specify that you want your transaction to be RBF:
You can set it do default to this by using walletrbf=1 in your bitcoin.conf file