After watching the final episode again, it wasn’t as bad as the first time. I guess the shock and disappointment has worn off and I’m in a calmer mood to analyse the ending.
Ji Mong left the palace with parting words to So that Soo may not be of this world.
Then we see the sun covered by the eclipse like Ep 1 when Soo was transported from present time to Goryeo.
We see So standing in the darkened Goryeo recalling what Soo said during their stroll.
Soo: If we had met in another world and another time, I was thinking how great that would have been. Truly, I could freely love you all I wanted.
Then cut to So wiping away the concealer and revealing his scars - symbolises he is giving up his throne and Goryeo life. He has no one left and nothing to look forward to anyway.
So: if we are not from the same world, I will find you, my Soo
Can we assume So himself (I like this better) and not his descendant will cross over to present time in search of Soo?
But of course, they could have added in a brief So-Soo meeting in present time: meeting of eyes across the room or back hug as a simple closure. But no, they have to end like this 😭😭😭