A Mum wrote:Let them laugh....lol.
I worked in a bank when they used to be green on green screens
Had perfect eyesight - no other eyesight problems in the family,
1 year later I needed glasses !!!
I blame the banks screens...lol.
Anyway - you do know you can change the brightness of your screen don't you Mal
Edit** Psyber you beat me to it
Ah yes, the flicker at 50Hz from those old CRT screens..
My first computer in 1987 had one of those. The later amber ones were not quite as bad.
When they became available I used the ones that could be racked up to 85Hz.
If your vision was getting marginal they pushed you over the edge, as fluorescent tubes tended to too.
If they were close enough to you, CRTs could give you a form of sunburn, and dry the eyes, although I don't think they could damage your vision directly, just aggravate any problems through those effects.
I used big screens and sat them well back on the desk.
It shouldn't be an issue with modern LCD screens