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It does still use SM2 by default -- you have to turn on FSRS manually. https://docs.ankiweb.net/deck-options.html#fsrs

You can set easy days via the FSRS4Anki Helper add-on: https://ankiweb.net/shared/info/759844606

And it also supports to postpone your backlog.

As others pointed out, SM-2 is apparently still the default.

FSRS would indeed be more interesting, as it seems to be heavily “inspired” by SM-18.