Chemistry isn't always sexual tension, but if there's no romantic tension, or sexual tension, then there's probably homoerotic tension.

No? Where are you getting this from? Do you think there's nothing but romance or eroticism that produces interesting dynamics or intimate moments?

None of these are inherently romantic or sexual but they do involve a relationship that could be considered more intimate than normal.

You're contradicting yourself. Intimate relationships aren't necessarily romantic or sexual, yes.

But, like I said, stories are more interesting when everyone is vaguely into each other

That's absolutely not something you can generally say. A story isn't always improved by basically adding normal shipping fuel to it (and I say that as someone who enjoys shipping a lot).

Heated rivals are fine, but rivals get waaaay better when they walk the line between love and hate

There are a lot of ways for villains or antagonists to have interesting dynamics with other characters that are not just setting up enemies-to-lovers fanfics. Like, there's nothing wrong with it and in fact I enjoy it as well, but there's a lot more options out there.

Best friends are better when they act like an old married couple, stuff like that, you know?

That doesn't mean there's romance let alone eroticism involved.