Many of us have the ability to entertain ourselves entirely within our own minds on the regular. None of us can snap our fingers and summon a chair from nothingness.

Do you know anybody who owns zero chairs?

There are cultures that don't use chairs.

The Japanese generally didn't use them (I think?) before they came into contact with European civilization.

I don't think any civilization could survive without entertainment though.

Many of us can sit on the ground or in a deep squat. None of us can snap our fingers and summon a book from nothingness.

sure, you can, many did, they are called authors

I did not say it was.

You can't rest your legs on an entertainment

Yet the entertainment I'm getting out of my chairs is limited.

But I think this is a false dichotomy: A comfortable armchair and a good book go well together.