static strips on radomes

Does anyone know more about what happened that static strips became a worthwile investment on combat plane radomes?

Back in 60s and some 70s fighters had cassegrain radar antennas, there were no static strips. In 80s most air force technology went to planar radar antennas, some even had a passive phased antenna – yet static strips were still not really present. even as far as early 90s they were hard to find – for example f15e, f15c/d didnt have them but later block f16s did have them. but then even the very new f15s, for example korean ones, dont have them.

Mirage 2000 doesnt really have them, yet rafale does. F22 has them. eurofighter has them.

Russians didnt use to have them, su30mki doesnt have them, yet su35 has then. pakfa has them. Pretty much all the new chinese planes have them…

And so on. There doesnt seem to be a correlation between radar antena technology. some planar arrays have them, some dont. some passive phased antennas dont have them, some do. So what gives? What changed that we started seeing those static strips used on some planes and not on others?