How to give previously stray cat independent outside time?

My cat used to be a stray until I adopted him last February. Before adopting he was always independent but would stay around the neighborhood and stick close to the house (it was a gated community of about 8 houses and he stayed inside the gate, other cats came and went)
I adopted him after bonding with him and got him dental surgery to get his teeth removed due to severe stomatitis.
I have kept him as an inside cat since his surgery (about 5 months ago). I give him about 30-60 minutes of outside time on his harness every day, but he is still always wanting to go outside. I also have an outside cat tent for him to hang out and watch birds etc without me. I feel bad that he wants to explore so badly but I am anxious that he will run away or get hurt because he doesn’t have teeth to defend himself anymore. Am I being inhumane keeping him confined to the house except for the supervised outside time? I don’t want him to get depressed or hate living with me. Or am I overthinking it? Should I let him explore in his own and trust that he will stay close and come back?

Cat: Male, neutered, ~4yrs old, US, no vet care needed

TLDR: previously stray (toothless) cat wants to explore outside, how can I give him exploration time so he doesn’t get depressed?