Just a few observations...
Such an accurate comparison.
With Sylvie, Loki doesn't know what to do or how to behave to show his feelings. Gods, maybe he even confuses sibling love he feels for her with a romantic love!
While with Mobius, he clearly knows what to do. He, Loki, made an eager step forward to him, and I'm sure, if they were alone, they would embrace each other warmly and tightly.
He, Loki, was the one who initiated that hug:
My point is, with Mobius Loki is perfectly aware of his actions. His love for the agent looks like an adult one, he is certain in it and and trusts Mobius to the point that he even let his inner walls down. I don't really remember Loki hugged someone like that in the MCU, really! He's definitely not a big hugger type of a person. He has trusting issues, so he tries to keep everyone (even his brother Thor) at arm's length. Never has he ever been an initiator of something as intimate and full of vulnerability as this hug. He almost cried there because of strong emotions he felt while hugging Mobius (Tom's acting here deserves all the awards imo):
With Mobius, Loki let himself be vulnerable. That's crucially important point: true love demands vulnerability from both sides.
While with Sylvie he doesn't even know what to do.
I mean, that scene with them sitting on the ground was so full of awkwardness and uncertainty. Sylvie even said: "How do I know you won't betray me?" He had to explain himself to her, ask her to trust him:
Still, Sylvie doesn't look convinced (as I see it).
With Mobius, he doesn't have to do all this. Loki feels more comfortable with the agent than with Sylvie and it can be clearly seen. It's awkwardness (Sylki) vs comfort (Lokius).
So, conclusion: Sylki does look like it is a forced relationship. I can't even say what it is built on. While Lokius is based on support and understanding. On the truth: Mobius showed Loki the truth about him on that screen in episode 1. It was painful for Loki to watch his whole life being presented with all its gruesome details, it was like a hard-to-swallow pill — but he accepted it because it was his truth. The same way it was painful for Mobius to know his truth about himself being a Variant. Loki was the one who told him about it, and after some time Mobius accepted it. So, Lokius is based on mutual honesty.
I do see Sylvie and Loki relationship as very close one. They are like brother and sister to me because, well, they are each other selves and also... Well, I still think their thing that they're having is all about love yourself first. You can't truly love another person if you don't love yourself. It is as simple as that.
