I think this has become way more complicated for your scenario than it needs to be. From what I understand you have solved the original problem, but now cannot “unfilter” as there is no “All”.
If this is correct understanding, here is the rest of the solution sticking with Bubble’s standard drop downs:
Step 1: Check within your drop down selection, there should be a blank “option” at the top of the list of options. This is effectively the “All” to negate the original filter. Like such:
Step 2: If the blank row doesn’t exist, it means you have this option checked on:
In which case, you won’t see the empty row like such:
Step 3: If you don’t like using the blank row as the “All” selector, then simply add an icon that when the user clicks on, it resets the dropdown. Like such:
PS: A while ago I also started experimenting with the above-mentioned suggestion using customized RGs and focus groups to mimic dropdowns, but after a long while realized that I can get everything I needed from the good ol’ Bubble standard drop down fella.