youre forgeting the problem that this game is already having: bugs, the bigger the game gets the more bugs will appear and the harder will be to deal with them, thats why i belive it should end by 1.0(rushed) and at best side stories might be finished after the 1.0 update, but the main story should end by 1.0 if he does want to finish the "side stories"
You actually have the wrong idea about how big this game is. Most of the game is occupied by graphics, which are stored in the img folder.
Now about bugs and the state of the game. The game from the first part is famous for random crashes, but recently having launched it on Nwjs, I noticed that it began to work faster and the speed of loading graphics in scenes became faster. Moreover, for the sake of interest and testing, I played from 6.20 to 6.27, and I did not have a single crash. Although usually this happens even during one small update.
Bugs, the truth is that any game and developer have them. That is why developers constantly release fixes for games with versions 1.01, 1.02, etc. There is nothing terrible about this, speaking of Sao, the game can be easily completed from beginning to end now. There are only a few bugs that can interfere, but they can be easily bypassed by simply launching the game a day in advance. The bug with lust is solved by editing it, the bug with teleporting to the hospital or getting stuck in the hospital at the moment where Inoda wants to show a photo is solved by simply starting the chapter from the beginning.
In general, the state of the game now allows it to be continued, and 5 updates will not change much.
Another thing is if Fujino really wants to implement everything that is conceived in the perks, then, as "13Gatsu777" wrote, this may become a problem.