Not really comparable, though both open world games.

I strongly dislike the Souls genre so TOTK wins by default, though it's also just a great game in its own right with insanely impressive technology and depth of gameplay, a huge amount of content, and a ton of charm.

The reason for the comparison is this: Two games which are generally considered the pinnacle of the open world genre, but take completely different approaches. It’s not really an odd comparison IMO (though I might be biased in saying that lol). It’s like comparing DKBananza to Astro Bot.

First of all, I'd like to say that I haven't played Tears of the Kingdom. Perhaps I'm being unfair to ToTK since I haven't had the experience.

That being said, based on my experience with Breath of the Wild (a game I believe to be very similar to ToTK), I would say that Elden Ring is undoubtedly a far superior game. I think it's absolutely incomparable, and I'd even say that Zelda: Breath of the Wild is an overrated game, worthy of a 90+, but far from being "the best of all time" as some claim.

Without a doubt, Elden Ring is better. IMHO

There is no open world genre.

Elite is open world game.
Ultima is open world game.
Sid Meier Pirates! is open world game.
Morrowind is open world game.
GTA is open world game.
FarCry II is open world game.
Minecraft is open world game.

...to name just a few known to wider audience.

And yes, TotK and ER are open world games.

All very different experiences.

The comparison seems a logical one to me; yeah, they're different experiences, but it's not like we're compared an FPS to a turn based JRPG here, there's enough similarity to where the topic makes sense.

Then I think OP needs to be more specific what aspects he's comparing.

The OP seems pretty self-explanatory to me; which was the better open world game.

As I said, open world is not a genre, and TotK/ER are not even in the same genre. Just like you can't compare BotW and Morrowind arbitrarily, even though are both open world games.

Yes, you can.

You're overthinking this; games don't have to be highly similar to compare them, every year we do a GOTY award where games from totally different genres are compared to see which is best.