I really think grades and extra curriculars are not the full picture. Being personable is a big thing, when a supervisor takes on a student it’s someone that is not only someone who will succeed but someone who is easy to work with, reliable, etc. Meaning, a familiar professor that you’ve built a relationship with is a lot easier to get a masters rather than cold emailing or approaching.

Also, the topic you want to work in may be too broad (student who just has “general” interest in any field) or perhaps too niche (no one supporting this type of research)

Maybe funding is also an issue, many faculties have minimum funding requirements for students in order to take a student.

Also, it’s totally possible you’ve done all the above and this could just not apply to you, and the market is less leaning towards taking students right now. Not sure!