To say shortly, storing 2FA TOTP codes in same password manager IS NOT THE IDEAL approach and is inherently less safer, then storing it into another app (which has different login/pincode for access, let's say Authy or whatever). So, when we open 1Pass and access password there, we need to open another app (i.e. Authy or LastPass authenticator or whatever) with other Pincode to get TOTP code.
So, we can have 2 entry points (which the attacker needs to overcome) and it's much safer than having everything just in 1Pass. THIS is the reason till date I am using other app for 2-FA TOTP codes. However, there is solution, which will help many users to make final decision to move into 1Pass fully (including TOTP). The solution is the following:
1Password Version: latest
Extension Version: latest
OS Version: win 10