Showing diffrent numbers of backlinks in GSC and Semrush

My website Have around 500 Backlinks Showing in google search console. But semrush showing different numbers of backlinks. Why??

Because one system’s crawling is different than anothers, and doesn’t happen at the same time globally?
Also possibly because one company has blacklisted different sites in terms of backlinks.

I bet if you saw Mozilla’s listing for your backlinks, it would be different as well.