No, they are not equivalent.
With the updates variant, the rule will be triggered any time the variable value updates. So even if it was already true and the value was set to true again, the rule would trigger again with updates as the value would be considered updating (eg. true → true → true = newly written, new timestamp).
That’s where changes (On Transition Only) is useful as you can indicate that you only want the rule to be triggered when the value changes rather than any time it is updated. With changes, the value would have to change to a different value before it would trigger again (eg. true → false → true)
Yes, the rule will execute each time the trigger condition occurs. As for if it’s a problem, that depends on your needs and rule design. You might consider posting in one of the other community threads about that approach if you are interested as I’m sure other community members would have suggestions.
While I can’t provide guidance around this kind of looping as it’s not a stable approach to looping and not something we officially recommend, there are some general best-practices you can use to help with this sort of thing to try to minimize issues:
That being said, we are considering introducing a first class loop feature and are looking for feedback from the community on what use-cases they are using loops for (in general, event driven rules are preferred, but there are some use-cases where a loop makes sense)