Why optifine can be used before version 1.16 and after it it is prohibited?

I agree with you, but still speedrans in the Random Seed category are accepted every day for several pieces, and there has been no reception of speedrans for more than 3 months.

Why do you think it takes so long to check and new results do not appear in the speedrans of the Set Seed category, have the moderators abandoned this category, and is there any reason to play in it at all?