Why do 2D lights never behave correctly in a built game?

Ive been working with 2D lights for ages, and theyve always worked quite well...

However, in the last couple months or so, theyve suddenly started misbehaving....

In scene view / game editor, they look perfect:

As you can see, it runs as its supposed to...

but when I build the game, it all goes full brightness, 100% intensity, no point light fade or anything: I literally cannot get ANY progress on my game because of this.

Ive tried this on around 10 different projects, each one has the same issue, and its driving me insane! LITERALLY no one has given me anything close to a solution. Its come to the point that Im considering switching to a different game engine because this is the only 2D lighting solution unity has, and it never works for me anymore!

I havent released an update to my game in over 4 months because of this one bug.... Please can someone help me out here.