I did an exchange in Japan and I was quite happy in a dorm but my friend had a different experience. I was in a girl’s dorm and was able to bond with the other students and make friends much more easily. It also felt like less pressure. While there were still rules, I didn’t feel as “watched” as I thought I might be in a homestay.
However my friend, who is a guy, started out in the dorms but he didn’t really care for the other students there and instead had a great time with his new host family.
I personally think homestays are a gamble and I liked the security of a dorm. But it may depend on the school, the rules and situation. Hope this helps!