Gating anything isn't new. Token make it easier to implement it. No more stitching together tools with another tool. Someone buys your NFT or token and bump they are in your group. Instantaneously. After the transaction went through.

Why this is stupid

There is nothing new under the sun. Even your little exclusive group existed in some form or another. Ok, this might have been a century past and you are adding new bells and twistles to the experience. But if you rip out all the fluff and decoration: You aren't doing anything special.

Why you should still do it

The horse your sitting on might just be a tiny pony, but you should still go ahead and put up a gate. Especially in this age of information deluge. By gating content or experiences you force yourself to curate them. It's not anymore for the masses, but for the select few who think like you or have big enough pockets to pay the price.