REST API: The consumer isn't authorized to access %resources. (2.3.1)

[corpsys]

Modify Config:

Allow OAuth Access Tokens to be used as standalone Bearer tokens: Yes

[jamesreeds6285]

In Magento 2.4.5 solution is to set

Stores > Configuration > Services > OAuth > Consumer Settings >

Allow OAuth Access Tokens to be used as standalone Bearer tokens option

to Yes

[plambateks60af]

No need to create an integration if you're using an admin token for testing