Oh, I definitely assume that, but I'm on the side of "you should be permitted to release / reuse source" and less so on the side of "you should be obligated to

Oh, I definitely assume that, but I'm on the side of "you should be permitted to release / reuse source" and less so on the side of "you should be obligated to release source." (That is, I see software copyright as a thing we should fundamentally not have just like software patents, and I see the GPL's copyleft approach as useful in a world with copyright law and I gladly write GPL software because we live in that world, but I don't think it by itself is justification to retain the leverage of copyright.)