Likely just a phase.
My 6yo will still eat with his fingers sometimes and we remind him he has cutlery on the table. he also was BLW and used a fork from 7 months, he can use his cutlery really well. I think lots of kids do this.
If he is very hungry or tired or teething he might not have the patience to use his cutlery well so that could be part of it.
I would remind him and ask him to use his cutlery time to time but not over do it, it really isn't worth battling over. Like any social skills or formalities LOs that "can" do something don't always want to or have the patience and focus for it all the time. He could be working on another skill in the background which is taking up all his mental effort and then one day he'll have a new skill and start using his cutlery again without you even doing anything about it.