HoMM3 HD is a mod (add-on) for the game Heroes of Might and Magic 3.

If the Mod becomes the sole primary and officially approved way to play

For me, it became that a long time ago, but what does "sole primary and officially approved" mean to you?

that's when you can just ignore it and do whatever you want :)

Which is exactly what I'm doing :D And no matter what assertions there were, whether official or not, they won't change my desire to play the HD mod instead of SoD. Even if there are a thousand of them.

Until then, the Mod is an authorized addition to the game, nothing more; and the issue of not being able to see another player's castles is precisely a problem for whoever has the mod running.

I absolutely agree with you there! This is currently a problem with the mod, which will soon be gone, thank God.

And only the problems of the stubborn "pure true SoD-ers" will remain, whom I couldn't care less about.