It's a slow system. MAL takes user submissions because they already have a big database and those submissions help filling the cracks. If you don't have a database to begin with it slows things down, especially if these submissions will go by trust-based. Doing this by randoms is also very risky.

However, I'm not completely oppose to that idea because it can be helpful for some areas. My suggestion is start with a basic dog tag system, where the anime name, alternative names, status (airing, completed), season and start date, studios (also licensors and producers), age rating etc. These information needs to be scraped for the fastest way to form a quick database, they are publicly available (even on Wikipedia) so it should be fine to scrape. You can even go full Wikipedia after got only the names. User submissions could be useful for the introduction / summary parts of the titles at this stage. For only names (and basic tags), you can scrape AniDB from this list. It's just a search query so shouldn't be against their ToS.

You can also check Kitsu for ideas, I like their DB request system. Pretty basic but can be done differently with the power of ActivityPub.