Is free feeding wrong?

Hello all, I am just looking for some advice on my little boy (JJ, 3 years old). I have had him since he was 3 and he has always been a great eater.

For the most part I had an automatic feeder for dry food that would give him a small portion twice a day (06:30 and 18:30) and then he would get an 80g tin of wet food a day, split in two and given at around the same time.

He was always good with this arrangement and his weight and health were always great on every vet visit. In the last year though his food begging got worse and worse to the point where he would be swiping at plates and constantly meowing for food anytime we went near the kitchen. We went to the vets and had a couple of checks done but there was nothing to explain it.

I had heard of free feeding and I knew it wasn't considered the best but I thought I would give it a try as it would allow him to eat whenever he was hungry. I thought he would just gobble the whole bowl in a day and it would be a failure but I feel I have had decent success with it. I filled his bowl on Thursday at 22:00 with 60g dry food and continued giving him the tin of wet food a day. The bowl lasted until today (Tuesday at 19:00) so he has had roughly 12g dry food per day which according to what I can find is definitely not over eating. And the change is major - he isn't begging - he isn't swiping.

I am just looking for general advice on opinions if this can be a negative in the long run and what those cons can be? Every style of feeding seems to have its pros and cons but I don't want to harm my little baby.