I have been very pleased with Ardour - only took me a few minutes to have my XLR mic go through a compressor / limiter / expander virtual rack effects setup for better screencasting.
The limiter just limits the maximum volume, and I'm not sure why he's using an expander.
https://www.gearslutz.com/board/so-much-gear-so-little-time/...
The main problem was getting high quality effects/plugins, paid or free. There are a couple, but in general life is much easier in this sense outside of Linux. That was 2-3 years ago, and hopefully things have improved since.
The Calf compressor and bass enhancer were very good. I'm seeing that a lot of plugins have been added in the time since I last worked with Ardour. Makes me want to start making music again :)