Possibly, maybe probably. If you dont want to degoogle, why use /e/os? Thats basically the explicit purpose. /e/is fills the same need as any degoogled ROM but is prepackaged on fairphone devices, no need to buy a pixel in order to use graphene. If you just want android, and the ability to use microg when you want and not when you dont, just use a normal android device.
Right, I think this is where we are misommunicating.
I use my fairphone as my daily. I also have to use OKTA, and stuff. And I dont use microg for them cause they don’t talk to google. I suppose technically the apps dont use microg, just like they dont use google.
The problem you are going to run into though is that google has baked itself into android that you need something to trick android into thinking its operable.
In stock android, you COULD have a workspace that only uses microg, but considering you otherwise MUST have play services… Why?
Alternatively, you can use microg to handle all your google bullshit to sign yourself in locally and actually use the services that require google without actually signing in to google.
Frankly, it sounds more like you want an Ubuntu/Linux (not android Linux) phone or something, but I’m not able to advise on that.