I have personally experienced the security disadvantage you mentioned. I used my Google login to sign into an email client. I immediately realised that the app was going to store all of my email data in their private servers. I quickly went over to the Google dashboard and deauthorised the app, relieved that they would only have been able to get my first few mails in this time. But the app retained access to my emails, even receiving new emails for some time. Probably because of something similar to a refresh token being revoked, but the access token still being valid. I wanted to stop the app from accessing my e-mails, but could not.

However, despite this disadvantage some applications just cannot afford the load of every single request touching the DB or cache. JWT makes sense for that particular use case when you are willing to make this compromise. Instead of every single request touching the cache, maybe every 1000th request does now, because of the token expiration time.

Another use case is when you need a very simple, stateless way to authenticate users and don't require revocation. Some Oauth providers don't give you the option to revoke access tokens, for example.