[marginalia_nu]

Sure. The energetic end of the visible spectrum is weakly ionizing, more so in the UV spectrum. But ionization is not why the bug starts smoking.

You can start a fire with a sufficiently high powered infrared laser too.

[nickff]

I think it's worth noting that a magnifying glass actually blocks/filters out UVB, and substantially reduces UVA. Feynman famously watched Trinity with only a truck windshield to protect him. https://en.wikipedia.org/wiki/Trinity_(nuclear_test)