Yeah, that’s because of the safety precaution.
Right now it’s deliberately hard in Bubble to build loops. The reason is that we’re sharing infrastructure between our users apps, and we don’t want a user running a workflow that saves a million things and impacts the performance of all the other apps.
We know this is a big limitation, and we’re working on two things to fix it:
-Dedicated hosting, so that performance-intensive apps can have their own database and do whatever they want to it without impacting other users
-A database system that’s more scalable, so that you can update a million things at once without causing an impact on the overall system performance.
These are both high priority goals for us right now and we’re hoping to have them ready to go in the next couple months. Once we have them in place, we’ll probably enable things like running a custom workflow on each item in a list, which would make it easy to do what you’re trying to do. Sorry for the inconvenience here – I know this is a painful limitation.