How should I introduce a cat to a new space?

I live in a large two story house with two roommates. We had a wonderful cat that lived well into her twenties. She is going to be missed for a long time.

The roommate who owns the house wants to get a bonded pair of cats. We have an empty room that I have been using as a creative space. Painting, wrapping gifts, working on TTRPG stuff, and I store the remnants of past hobbies here.

When we get the new cats roommate wants to clear out the room so the cats have a place to acclimate before they have the whole house to run around in. I am fine with this as I can shove evetything into a closet in 10 minutes, and pull it out almost as fast.

BUT, I have one worry. I thought this locking them in a room thing was for when you add a new cat to a home with an existing cat. It lets everyone get to know smells without fighting. In the past I have always brought a cat home and immediately let them explore. They sniff everything, hide for a week, then are pretty much ready for pets.

1. Have I been doimg it wrong and thus being a poor cat dad?
2. Was I doing it correct and now we are just planning to lock two cats in a room for no reason? I hate the idea of isolating them when they could be exploring, and being stimulated for no reason.