It's not that your 16yo doesn't like compliments, he's just being embarrassed. Not a valid reason to stop them! Spare him ,and don't do a huge fuss around his mates, but keep complimenting when deserved. They need to hear it and know it. It sticks, even if they are all awkward about it now.
I know what you mean - I try and make an effort to praise good behaviour and sometimes it's well-received but often my son will deny having done the kind/thoughtful/helpful thing that I am praising him for and get in a strop if I mention it again.
If I catch him in the middle of doing something nice, he will often stop if I mention it, and if I refer to something I noticed earlier in the day he will sometimes say that he didn't like doing it and he will never do it again, even when it was something entirely motivated by good intentions on his part (as opposed to something I have encouraged him to do). I've tried different ways of saying things and describing his behaviour in a range of ways (e.g kind/thoughtful/good friend/creative/imaginative/hard-working etc)
It's hard to know whether to carry on praising him or not - I do, but not sure if that's for my benefit of feeling like I'm doing the 'right thing' or for his because I want him to know that I do notice his good behaviour. He is generally incredibly sweet and thoughtful although he can be excessively 'boisterous' and occasionally behaves outrageously badly so I do want to balance the remonstrating with praise but it's hard to do when I know that he finds it infuriating for some reason.
I found firm but fair, limited screen time and lots of love an attention was the way to go
I use all of those things in conjunction, as do most people I imagine. Praising good behaviour doesn’t mean people aren’t firm and fair, allow unlimited screens and don’t give love and affection. Those things aren’t mutually exclusive.
My eldest is like this - and I think he's probably got it from me. Sometimes at work the higher-ups start sending out thank you emails (copying in the whole team) for perfectly normal pieces of work - and it winds me up. It's nice to be acknowledged, but for me that sort of thing devalues the thanks I get when I have gone the extra mile. My son does like being praised for something that is genuinely good. (Of course, it may also be that, like the higher-ups at work, I am rubbish at faking the sincerity of genuine praise for normal behaviour.)