I'd totally buy that it's not meth, but there's gotta be something other than housing prices, right? I mean, housing is up since the pandemic but the homeless camps are waaaay up. I don't have deep knowledge of LA like you; just visit a couple times a year. But my friends who live there say it's gotten to a place of intolerability in the last 18 months or so. There were rumors of other cities sending their homeless there, but I have no idea if they're just rumors.
In fact, LA has only 16 mobile toilet stations for its 36,000 homeless people. To make matters worse, the city hauls away the mobile toilets at night, leaving the homeless no choice but to go on the streets. As you might imagine, COVID made things worse. My adventures in Los Angeles started in the late '90s. The Soylent Green atmosphere was striking even back then; Los Angeles basically allows the homeless to accumulate cruft and detritus for two or three months, then comes through and sweeps out all their shit unannounced. It's part of their public custodial approach. It's very much the way Los Angeles handles all its civic sanitation: move your car twice a week or we'll ticket it $80 because of "street sweeping." Will the street sweeper actually come through? Yeah maybe once every couple of months. Will the cops come through to ticket? without fail. One word describes Los Angeles' relationship with the homeless: adversarial. I have never spent time in a city that hates its homeless as much as LA. I'm very happy to report I have no first-hand experience here but I'll bet the added stress of the pandemic has not improved that relationship. Seattle's gotten pretty bad. We put spikes where the homeless sleep, blast pink noise where they congregate. Our homeless have gotten salty as a consequence. But I mean, we'll let it get pretty bad before we do anything. Los Angeles? LA cracks skulls because it's fun. "Place of intolerability" has been Los Angeles for as long as I can remember. The city is openly hostile towards its unhoused, and the unhoused are openly hostile in response. It surprises me not a lick that things have gotten awful during the pandemic. 
In one act caught on camera, a homeless man is seen waking up on South Hope Street. He unbuckles his belt, walks over to the front door of a business, pulls down his pants, and defecates right on the door mat in broad daylight.
A measured response: https://www.nytimes.com/2021/12/16/opinion/homeless-drugs-meth.html Interesting that WV has simultaneously one of the highest OD death rates and lowest homelessness rates. Makes sense, but I've never heard it put that way.
That editorial was a thousand words of waffling followed by It's NYT hand-wringing distilled to its purest form - paraphrase the article, add nothing, and whatabout to questions no one has asked. your point was "clearly meth is driving the shitty homelessness crisis in LA." My point is "LA's shittiness is driving LA's homeless crisis, meth or no meth." Quinones' point is "there is anecdotal evidence that biker meth is mean because homeless meth users are mean" while Kang's point seems to be "as a journalist for the New York Times, I am duty bound to cast aspersions on all other journalism while simultaneously refusing to take a stand about anything." Quinones' whole schtick is anecdotal evidence. He's an ethnographer. Kang's whole schtick appears to be "I'm going to pretend my readers asked me if they should pay attention to an Atlantic article because I'm too cowardly to opine on my own. Here's my lack of opinion." Sorry. My hatred of the New York Times grows stronger every day.So, my answer to the reader’s questions: Quinones’s concerns over mental health and meth should not be ignored: If you spend a lot of time in or even near a homeless encampment, you’ll find people who seem to be experiencing the psychosis Quinones describes, but you’ll also see families who have been priced out of their apartments or who have had their lives derailed by the pandemic.