" I can't say I ever encountered any lag or such issues as you're claiming it has and I read it to completion." You clearly haven't played the JP version.
First is the startup menu, when every .jpg of the girls is coming together, it is laggy.
Second is when Sachi has her robots behind her, every time it starts her dialogue it lags for a second, and more instances of it happening when there is a magical circles and so on.
You don't have good base of comparison, hence why maybe it doesn't look laggy.
I don't know if they even updated the Steam version( mine is on 1.00) I know for sure that the JP version has to 1.08
"Console version of games being ported to PC is nothing new and that doesn't make it half-assed as you claim."
Sure it isn't anything new, the problem is always the optimization and in this instance is bad, but that also isn't anything new lol