Greetings, and welcome to the community!
To be honest, in my experience, whether a smaller bike is needed at the outset, or simply going with the bike you really would wish to ride, all depends upon the new rider and their natural ability. I've had friends over the years who began on a larger bike and did just fine - they had a natural "feel" for riding, and experienced no problems. On the other hand, I've had friends who were not so naturally inclined to riding and who accidentally dropped their bikes a few times in the beginning. Needless to say, handling and picking up a smaller bike is very different than a big cruiser. Everyone I've known, though, who began with a smaller bike swiftly progressed to a bigger bike - it is the "nature of the beast," as the saying goes. So, to me, watching many new riders over the years it is all a question of the individual and what's best for them - the answer to this question can be different from one person to another, or so it seems.
If a person is comfortable with a bigger bike at the outset, I'd agree with everything that's already been said - that would be my preference, and it's what I did. I just bought the bike that attracted me at the outset, and that was twenty-eight years ago - and many bikes ago.
I'm sure you will have a sense of what's best for you.
Good luck finding your bike!