If time and willingness were completely unlimited commodities, having all original dumpers check all of their games for that space could theoretically be a possibility. But neither are unlimited unfortunately. If people truly want to check them, sure that's great, obviously it will improve accuracy. But I don't think it is significant enough of an issue to reach out to everyone and have them do so, when there are...more pressing things they might be attending to.
Since protocols like this have changed over time, and even currently accepted protocols haven't always been consistently communicated to both dumpers and mods, there will definitely be inconsistencies like this in the database.
There are countless "issues" with the mould codes in the database such as this. For example, many people submitted mould codes by adding "IFPI" even if it wasn't on the disc because that's what they were told to do. Some people were told to capitalize IFPI even if it was lowercase.
I do think it's good to be consistent going forward, and I certainly have no problem with correcting the previous inconsistencies as they arise, but I doubt in this case that people are going to want to go back and check all of that, and I'm certainly not reaching out to them to do so because I think it is a...secondary / tertiary / lower priority issue at the moment.
I verified even some of Fireball's Saturn discs where he had a space and I didn't. Who knows whether his original was "correct" or added under the previous protocol.