Out of 1,348 people, 7 really isn’t that large of a number, but in the context of an error page, there shouldn’t be that many people reaching it at one time. Granted, malicious activity on popular websites is always a possibility for boosting this number, but I wouldn’t use it as an excuse before investigating.
It’s impossible for me to tell why people are erroring, but I know that there are logs that can be checked. Depending on what the log says, it could be something that actually needs to be fixed.
One reason this number might be higher now is the release of the new student portal. The old student portal still exists, so there shouldn’t theoretically be any problems with no longer existing pages, but I have already run into a couple of issues with the new portal myself. They weren’t 404 errors, but anything is possible.