Someone else already pointed out this is LWIR, not Mid wave(I look forward to the day we get cheap MWIR cameras! We'll be able to see heat trails behind jets- and gasses like no tomorrow- you tend to see through 95% of the with LWIR)

But large apertures? Are you thinking of the longer wavelength? For near infrared, this is a thing- and other night optics....and things like NVGs which use Near infrared

But, this isn't ...a thing for MWIR/LWIR, and not necessarily for SWIR either

The reason not ALL thermals have to be cryogenically cooled- is microbolometers - that's the key.

- I own a bunch of uncooled LWIR cameras, that i use- and NVGs as well