Did I miss the window to get my cat a cat friend?

I've only had cats in pairs growing up in a house before, and this was the first time getting one cat alone. I am in a small apartment and did not think there was enough space for 2 cats to get a break from each other or do proper introductions.

I was originally going to wait until I moved to one with more space to get 2 cats together, but caved after being so lonely during the covid lockdowns and missing having a cat.

Now my cat is 5 years old. He is wonderful! I love the little guy. He is so full of personality, is such a cuddlebug and loves to hunt his bird toy.

But he "cries" a lot, will sit in a hall and meow. I have read this means he is bored :( I try to play with him, but sometimes I am so tired from work. I also worry about him being home alone when I am working or out.

Now, I've also heard some pretty bad introduction stories. Someone I know has to keep their cats quarantined because they are just violent towards each other. Other people say the cats "tollerate" each other, but never really "became friends".

I am worried I waited too long and now my cat is too grown up to enjoy having a friend, but is always going to be missing that companionship!