Hangouts Meet is taking over for G Suite Video Meetings and it's not too hard to see why Google is looking to push administrators and anyone else whose businesses use G Suite tools to make the switch. Over on the Google Support page Google is listing off various differences between the two different tools which, provide essentially the same exact function. It's doing this with a side by side comparison to let users know what the differences are so they can make an informed decision of which tool is the best fit for their own personal needs. One of the first things Google points out is the difference in numbers you can have in a single video call. With G Suite Video Meetings you're allowed up to a maximum of 25 participants, whereas Hangouts Meet allows up to 25 G Suite Basic and Business tiers, but then bumps that up to 50 for Enterprise and Enterprise for Education.
While some may not be keen on changing things, Google has already started sending out notifications to administrators about the shift, stating that classic Hangouts video will be switching to Hangouts Meet on May 21. This gives anyone with a G Suite basic, business, enterprise, or enterprise for education account who is still using classic Hangouts video a little less than a month to get things in order, though there really isn't much that people will have to do as everything will still work the same.
In fact there is likely to be no change at all for anyone. After May 21, when creating a video call in Gmail, G Suite will just start defaulting to Hangouts Meet, so there is literally nothing users will have to do for the change. That said Google is also offering administrators the chance to postpone the switch by up to a month, but after that the switch is mandatory. Considering all of the upgraded features that Hangouts Meet offers, it's unlikely that many will have trouble moving over from the older option with less features.