You are not doing anything wrong! Some babies just find sleep comes more easily to them than others. My first was a bit like this - would sleep in pushchair, etc, but at home would only feed to sleep, nap when held, etc, until around 9 months. Worst period was 3-7 months when he woke every 45 minutes on a bad night. I was on my knees.
I hate to say this but my first would not self-settle until he was around this age or slightly older and would then only do it when I wasn’t around, eg he would go to sleep in his cot if Daddy was sitting with him but would scream if I was around as he preferred to be breastfed to sleep.
Might be worth thinking about what you want and whether it’s realistic, then picking one thing to try - eg getting him to nap for longer in the day, or breaking the feed to sleep cycle if that causes you a problem.
So if controlled crying doesn’t work for you, other options include:
- gradual retreat (more gentle then controlled crying).
- sleep consultant
- GP to check nothing physical disturbing him like reflux.
- co-sleeping if that gets you more sleep.
But don’t beat yourself up. I spent months trying to figure out where I was going wrong - and when mine got to about 2.5, he became a dream sleeper who went through the night without a murmur. Most people have good or bad periods with sleep, often when everyone else they know is having the opposite.