I am a newcomer to OPNsense, but I wanted to add that I am similarly confused by this. After running the migration assistant, including the 'delete legacy' step, I am left with collapsed menus of "automatically generated rules," "floating rules," and "rules from automation" in my legacy rules menu. These are seemingly updated when I make new rules in the new interface. My initial understanding was that the legacy rules were just updated automatically based on the rules in the new interface, and basically serves as a vestigial display. However, there are very many rules that are autogenerated and shown in the legacy menu which are not present in the new menu, which is confusing.
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