Above is an example of one such collection. The Montgomery County, PA Deed, 1784-1866 is not found in the online collection list (at least, not as I post this - it could get added any time), you can go to the list and narrow it down to Pennsylvania and see there is no mention of any records of deeds. Yet if you search for it in the microfilm catalog, you'll see the camera icons (circled in red in the screenshot above) you can click to view the digitized images. Of course some collections may have restrictions on them, meaning you can only view them from a computer in a Family History Center or affiliated library, but it's better than nothing/waiting for microfilm to come in.
What this means is that there may already be collections you need that have been digitized, you just need to do a little more digging to find them. So there may be more available now than you realize. Of course, if you'd rather wait till everything is indexed, you're welcome to do so. But the end of 2020 date is just for scanning everything, that doesn't even include indexing. You could be waiting much longer than 2020 if you wait for everything to be indexed. So I would advise regularly checking the catalog to see if there's any collections that have been scanned but not yet added to the collections list or indexed.