It requiring extra development is the only explanation I can think of for why almost no games come with native linux builds, not even single player ones.

Because developing for Linux takes time, and it doesn’t have a large enough market share to be considered worth it.

That’s the one I remember being skeptical of, since it also corresponded with a drop in players overall as the game aged.

The Linux having an over representation of cheaters one.

That’s a claim I’ve heard, but never from a credible source. Are you aware of actual data backing that claim up?