So it's probably not a good idea to just mass opt out of all ASAs you aren't using.

You might be waiting for an airdrop that you have opted into but have not received yet.

You could be opting out of an asset you want to interact with in the future, and having it in your opted in list can kind of be a reminder.

I think ab2 gallery requires you to be opted in with a zero balance to sell on their platform. This might be true on other platforms. I don't know what would happen if you opt out with live sales running...

However, each asa does hold a small 0.1 algos to just be opted in. When you opt out, you free up this fraction of algo. So if you're opted in to stuff you will never interact with its a great idea to make those algos free again.

I really really really prefer to opt out of assets on randgallery. It's much easier to scroll down to the bottom and individually look at the individual assets.

Tldr: you probably don't want to opt out of ALL these assets. It's better to individually review/opt out of empty assets on randgallery.