What steps will reproduce the problem?
1. go to https://fippo.github.io/simulcast-playground/chrome (or clone https://github.com/fippo/simulcast-playground/commit/06abb9799bf7d33f0018d1b4d46e1ec766e39265)
2. watch the local framerate graph

What is the expected result?
the framerate is around 30fps

What do you see instead?
the framerate is 90fps

What version of the product are you using? On what operating system?
69.0.3493.3 on linux

Please provide any additional information below.
The sample is using simulcast and presumably adds up the individual framerates.

This is the wrong semantics as outbound-rtp stats are per-ssrc. Also there is just one ssrc showing up while three are sent.