"Keep friends those you love close to you."

[Cyberman]

What does that actually mean?

[Mr357]

What does that actually mean?

Don't treat your friends and family like shit. At some point they'll be all you have going for you.

[Yokosuka]

That literally means you have to fight the Dragon final boss with all your friends on your side including Nozomi and Fangmei after they mastered fireballs in Shenmue V. Don't forget Shenmue was initially a RPG.

[amiga1200]

^^
what it means, at least at face value.
as for the source and state of mind of the individual that coined the phrase, who knows, we can speculate?
...
Mr357 put it in plain view, sheer clarity. (and it's also a variation on that old piece: treat others how you want and expect to be treated.)
...
i see it another way, still protecting from damage.
don't give them enough rope to hang themselves with, for betrayal is a blow seldom recovered from, merely coped with.
be responsible for your OWN actions, and offer help to others if possible, but draw the line.
just because a problem is shared, doesn't half the fucker, simply copies the burden.
...
if you value friends and family, don't tax them, or stress them too much, dependence has a severe price.
never take them for granted, just equals.

[johnvivant]

just speculating, but i think Iwao didn't take care of his friend (Zhao Sunming?) as well as he should have, and consequently he followed an evil path, and Iwao either had to kill him or allowed him to die in some way.

Maybe this predicament is repeated in Ryo's and Ren's relationship, so hopefully Iwao's advice will prevent Ryo from making a similar mistake.

[ReeceKun]

just speculating, but i think Iwao didn't take care of his friend (Zhao Sunming?) as well as he should have, and consequently he followed an evil path, and Iwao either had to kill him or allowed him to die in some way.

This ^

However Ryo proceeds to ignore everyone and their advice and goes off on his own insane egotistical revenge rampage .. and capsule toys