Basically maybe to implement feature that being spotted after firing main guns is harder to detect for any type of attack aircraft ( by that I mean anything launched from a CV ), and make actually spotter plane more beneficial for spotting actual ships that maybe be firing ( basically they can spot further ships that are firing their main guns ). After all I think that pilots in IRL scenario or in a game spotter plane would be dedicated to spot what is going on the sea coz that would be their only job realistically looking, compared to those who are flying in squadron trying to keep communication, keep everything in line not to hit anyone, focus on the target how to approach and watch out for aa too, on top off all that they are able to spot all the ships that are firing, making actual spotter plane irrelevant.

Just my little rant, feel free to comment and discuss on this topic, CVs are broken and will stay that way, but I feel like what annoys me from cv is if I'm not being harassed by it I'm being spotted if I fire my main guns regardless of ship class.