Are you familiar with building from source?
If so, there is now a release candidate for Audacity 3.0.0 available (see: https://forum.audacityteam.org/t/audacity-3-0-0-release-candidate-available-for-testing/60573/1)
Given that elementary OS is based on Ubuntu, these build instructions should be pretty close: https://forum.audacityteam.org/t/building-audacity-2-4-2-on-ubuntu-20-04/57719/1