Kanye West shouldn't just laugh off gang threats in L.A. ... so says Matt Barnes who says the real gangsters in Los Angeles don't mess around.
The ex-NBA star was leaving Catch when we talked about Kanye's appearance on "TMZ Live" -- including Yeezy's reaction to Daz Dillinger's recent call for the Crips to "f*** up Kanye."
"You gotta be careful," Barnes said ... "They don't play out here with gangs so you're treading on thin ice."
Barnes also reacted to Kanye's confession about getting liposuction -- and says it shows Kanye is "not in a comfortable, secure place as a man."
Barnes says a lot of what Kanye is talking about these days -- from Trump to his views on slavery -- are "bullsh*t" -- but he believes the old Kanye can still be saved.
"I know that man is in him still."