Google Meet will now ask you to leave empty calls.

When you’re the only person in a Google Meet for five minutes, you’ll receive a prompt asking whether you want to stay or leave the meeting. If you don’t respond after two minutes, you will automatically leave the meeting. 

And also it will prompt you if you are waiting too long to get into a meeting as shown below as well.

Currently, this feature will be available to desktop and iOS devices only and will be available for Android users soon.