As an EVE veteran, I can tell you straight up that you're wrong. This is just your opinion, and it doesn't matter how many people share that opinion, without qualifying your opinion, it remains only an opinion. And an opinion not grounded in substantiated fact is little more than a delusion.
Facts about what exactly? Of course this is just opinion, from all of us. There are no facts that make personal preference correct or incorrect. People who want a more dynamic and interactive MMO are not getting it in Elite Dangerous, and the online component to the game will stagnate because of this. That's basic logic, nothing more and nothing less. You don't need facts or a doctorate degree in mathematics to know that 1+1 = 2.
Now here's my qualified opinion - Elite is shaping up to be one of the best quality open-world sandboxes ever, a very LARGE open world that given more time and development, will be a hot contender for EVE Online's title. It already has player interaction going on - I know I've had a very large bite of it. If you're not getting any, I can quite matter-of-factly conclude you aren't looking.
It absolutely could get there if they add meaningful interaction (trading, group missions, group loot) meaningful PvP (modules lost on death that makes pirating worthwhile) meaningful exploration (rare resources and technology to find) as well as crafting, player control of planets/systems through personal stations or clan stations, and a player driven market. With all of these elements, elite dangerous would be eons above EvE online. But, it has none right now. Right at this moment, it's a single player game. The MMO part is essentially pointless, especially since you can switch to solo mode and back with the same character. It's not even an alternative profile, that is insane and that fact alone invalidates this being an MMO at all. Imagine in EvE being able to remove all other players, the danger and difficulty of the game, and then switch them back on later after you've obtained the good stuff easily. No. That isn't right.
Your mistake is, you're trying to pretend like there are only two kinds of sandbox, and there is no room for a third. Even if Elite doesn't fit into the two categories you tried to define with your subjective opinion of what those categories are, why can't it have its own and be something new and unique?
It can, but it won't appeal to anyone new. Unless I am missing something. Why would anyone care about other players in elite dangerous as it stands now? There's no reason to. It's a single player sandbox. It can absolutely change, but that's for time to tell.
You are not a special snowflake and you don't get to make demands, especially such misinformed ones
Actually we're all special snowflakes. We're all unique (quite literally). That doesn't mean we can be rude or make demands, fortunately he wasn't. He was just stating his opinion on what he thinks the game needs. I don't know how you construed that to be a demand.