You know your baby. He wouldn't be going back to sleep if he was truly hungry. They go through a lot of regressions from 4+, even one at 6 months so it could be that that's waking him, also teething or just looking for comfort in you or the dummy. Definitely don't think you're depriving him. If you are worried you could do a bottle as a test. My daughter at 6 months was waking once a night for a bottle. Also just to add my daughter is now 26 months and though she has slept through the night a few times, most of the time she's up at least once so it may be a thing that just need to deal with. Also when you start weaning, you may find that sleep gets better or is interrupted more. It's a guessing game!! X
Have you had a look at the feeding guide for the formula you are using? I know it's just a recommendation, and every baby is different, but if he is having the recommended amount for his age/weight during the day, then i would say you are fine to let him sleep/not give extra during the night.. it could just be a comfort thing and the routine he has gotten used to. As long as he is still gaining weight as he should, and isn't showing signs of dehydration/constipation then he is probably getting enough food, and like you said, if he was really hungry he would cry until fed. My little girl has slept through the night (started with 6-8 hour stretches) since around 3/4 weeks old, and my midwife said as long as all the above was being met, then it was fine to leave her. She now sleeps 8:30pm - 7:30am but does sometimes wake like your little one and babble, but goes back off after a few minutes/when given a dummy.
It's still very normal for babies to want to be fed during the night at this age. My HV advised around 10 months ish is when they shouldn't need it anymore (that was the age my son stopped). My girl is 7 months and has 1 feed during the night, which I won't deny her at this age, whether she needs it or not
You know your baby better than anyone. My daughter used to wake 2 times a night for milk, so I would just give it her. I was always worried she would be hungry. But if he doesn’t put up much of a fight then he’s probably fine. Sleep changes sooo much though, so be prepared for growth spurt/teething, baby will probably want more milk and wake a lot more frequently in the night. Follow your gut :)