So in the beginning there was Android Pay, which later became Google Pay in the US and Europe.
For India, Google launched an app called Tez (and later renamed Google Pay) there which was more adapted for the India market, doing things like phone number identities and UPI integration.
This worked so well in India, that they promoted the head of the India app to be in charge of payments everywhere, and so his plan was to replace the global Google Pay with Indian Google Pay. They started with this in the US, and it flopped hard, both in terms of uptake and reviews. It turns out in many non-India markets (including the US) people don't really want to accept the tradeoffs of phone number identities for anything that doesn't directly compete with their SMS app.
So the leader responsible resigned, and the new leadership instead updated the old global Google Pay as Google Wallet. India stuck with Google Pay (formerly known as Tez) since that worked there, and the rest of the world never moved from Google Pay (fka Android Pay) to Google Pay (fka Tez), so only had a single Google Pay at one time. However, Google had now split their userbase across two apps so was scared to shut either there, so the US stayed in limbo for two years.
This is now resolving the US based limbo by shutting down Google Pay (fka Tez) in the US, so that the US joins Europe in only using Google Wallet (fka Google Pay fka Android Pay).
In short:
Before:
- India: Google Pay (fka Tez)
- Europe: Google Pay (fka Android Pay)
- US: Google Pay (fka Android Pay) and GPay (fka Tez)
After:
India: Google Pay (fka Tez)
US & Europe: Google Wallet (fka Google Pay fka Android Pay)