I try to avoid doing any processing in google sheets if at all possible because there will be a delay.
If all of your checkboxes function the same for each row, I would maybe consider restructuring your data. If it were me, instead of multiple columns for the checkboxes, I would create a new sheet and put each of those column values into it’s own row. This wouldn’t be duplicated date, it would only contain 100+ rows to match the number of columns you have. This way you can display it using the checklist style inline list. With this you could have a Relation to that new sheet and only look for true values. Then you can create a Joined List column of all the true values that would be in that relation. With that, you can then have a button or something with a Set Column action that would write that joined list to your existing sheet.
Now this does cause some issues when using the checklist, because each of your existing data rows would show the same checked items. This is where you need to take it a few steps further with some compound action logic that would probably be better explained in the thread below. I’m doing something similar where you can select multiple items and it sets an ID on each item in a list. This marks it as selected and changes the image from red to green. As you do that, you’ll notice that it’s also building a Joined List of all the selected items. The delimiter in my case is 2 spaces and a carriage return, but you could use a comma (,) or pipe (|) as your delimiter. With a save button, you could write that joined list to a basic column through the set column action. With that delimited list, you can then expand it into an array using the Split Text column and then use that for your lookup. You could write a row ID of the current row you are viewing to your user profile when you open that row, then write that value to each item you “check”.
Without knowing more about your specific use case, it’s hard to say how well this would work for you. I know the above description probably isn’t very clear, but hopefully the example below makes more sense. I think it would work for you, but the tricky part might be if you ever need to go back in and modify the checked items. I’m sure it’s still doable, but with a little more logic involved.
Take a look and see if some of this makes sense. Doing it this way would allow it to easily scale in the future if you ever needed to add additional checkbox items. You also wouldn’t have to mess with 100+ components that have to be configured on a screen.