Legit went to school with a girl who thought this was ACTING and it's how she attacked every line. She tried to get into an agency but nobody would take her. I heard she got 100% for her grade in Drama at the end of year 12 and I really did a hard think over how that must have happened.
It's what would charitably (and politely) be 'acting for the back rows' If the people who weren't just church randos and had "experience" (ie high school drama) they might not realise that there's a completely different style of performance for stage actors and camera actors.
I only did one minor professional theatre thing, but I did a fair bit of camera work and it's all about internalising your feelings. You emote with your eyes, with the angle of your mouth, with a small furrowing of your brow. A little goes a long way on camera.
On stage, you have to act big so everyone can hear you, see you, and understand how you're feeling. So, stage work is about externalising everything. Dramatic faces, sweeping body language, projected voices. It takes so much talent to externalise without being over the top, and to act on both a micro and macro level. It's why I admire broadway actrors above all others.
Usually amateurs have had no real professional training to speak of, and if they have it's often not the best quality. They don't know that performing like that is for church plays, not for movies. They've probably only ever done stage work before, if anything, so they would have no idea how much you have to dial it back for film.
IDK. Can't really blame them for doing their best with a director who has no experience with actors.