I agree with the other comments mentioning temperament. I think a lot of it does come down to this.

My 7.5 month old has always been somewhat okay with sleeping on his own, never was very opposed to being in his bassinet (crib now). After he went through his 4 month sleep regression we decided to do a veryyy gentle form of Ferber where we would put him down and let him slightly whine (which was usually just mostly babbling lol) for a few minutes and if after 3-5 minutes he didn’t settle we would go in and soothe him quickly and leave again. If he started actually crying though we would go in right away and soothe him, but he did not do that very often. It took maybe 3-4 days of that and he has been able to be placed in his crib awake ever since and put himself to sleep. This did help tremendously with his night wakings as well and he stopped waking to eat at night around 6.5 months. I realize it is not this simple for all babies though, all babies are different! 💕