For what it's worth, I run Microsoft Teams in its own isolated Chrome profile with almost no extensions (definitely no adblockers). It's been sitting in the background 99% unused for the past 4 hours and is currently wildly fluctuating between 500 and 850 MB of RAM usage + 8-12% CPU usage, despite not even being the focused tab in said Chrome profile.

That being said, I wouldn't be at all surprised if a content blocker made it even worse. It's just... not very good software.