Yeah its the same with CCTV lenses as it is for Dslr cameras, sure you can get a cheapo one that will do the job, but you can allso get a lens with the same overall specs and pay 3-4 times more.
And yes the expensive lens will be better, question is if a non pro user can see that in the output.
I have tried a fjew lenses on action cameras and dashcameras and for CCTV use, and there is no doubt you get what you pay for.
You can get a cheapo 5 element lens with lenses made of plastic, of you can get a sweet 7 element lens with lenses made of the finest glass.
The cheap 5 plastic element lens will be put together by a trained monkey with a hammer in a garage in China, the expensive glass lens will be put together by trained professionals with computer guided machines installed in a aerospace graded clean room, and working with much smaller tolerances.
For a long while it have been common practice to use cheap lenses on cheap dash-cameras to cut corners, and the end result will be a poor camera with poor performance.
As i said above the lenses is M12 fine thread( 0.5 mm pitch ), simmilar to ones used in CCTV cameras, and you can get lenses from 15 dollars and up, just dont get too high hopes for the cheap ones out there.
Just google Lens + m12 or Lens + S-mount, and look for megapixel lenses with or without IR cut filter.
For a 4K camera you offcourse want to look for lenses that can handle the 12-16 megapixel a 4K sensor is, not sure a "small" megapixel lens intended for 2 - 3 megapixel sensors will work.