ROB: Since you don’t know me you wouldn’t know that in my shiurim I regularly take issue with seforim that twist Halacha to support their persona agenda. Usually they are being dishonest creating new chumros, in this case it is a kula.
Reb Moshe clearly demonstrated respect for the rule of koach d’hetera adif, despite occasional chumros found throughout his teshuvos and not limited to Hilchos Shabbos. If he found no grounds to countenance any leniency regarding electric lights on YT, it bears mentioning.
I’m not relying on the Chazon Ish, the issue here is not boneh. However I don’t disagree with him by calling him names, I would instead analyze the sugya as Reb Shlomo Zalman Aurbach does in Minchas Shlomo.
However if you consider an electrical current to be fire that turning on a light is ma’avir, you must consider all electrical fans alarm clock etc muktza as a basis to the current. You can’t pick and chose contradictory kulos. Accepted understanding is that only the glowing filament is a fire not the current,therefore turning on a light is creating a new fire.
R’ TP Frank is certainly an excellent source to rely on, but not when he retracts his heter to rule it is assur. The Aruch HaShulchan is also a wonderful sefer, but an unpublished letter on a topic he was unfamiliar with is not something to rely on, especially if no one in the following 100 years concurred. The Maharsham (not Maharshdam who was much earlier)is also wonderful source to rely on, but he was not quoted in the article.