i think it would be pretty lame if they were to deprecate monobehaviour as a whole. the community has already developed quite a bit around it, it's easy enough to understand that newbies can get into it and begin to learn scripting. if people wanted to solely concentrate on visual scripting, most would just choose Unreal. i haven't really spent much time investigating ECS, but it seemed slightly convoluted from what i've seen. granted that was only their "hybrid" ecs system, but it just seemed like standard monobehaviour with extra steps.