Just highly unreliable and could be quite misleading. I know...

Just highly unreliable and could be quite misleading. I know everyone is looking for a way to Gage growth and popularity but the best way by far is company reports sales and revenue.
If you wanted to validate google trends as a reliable source you could compare past company results . Ie half yearly (Afterpay/affirm) against each other. Then find corresponding snapshot on google trends to see if they match up.
I do appreciate the effort.