This is part of a larger political astroturfing campaign. There was a very comprehensive post on reddit about it when this garbage starting flooding into small subreddits. I'll see if I can find it.

Found:

https://www.reddit.com/r/videos/comments/qdf9bp/comment/hhp5s4u/

https://www.reddit.com/r/OutOfTheLoop/comments/pj395z/whats_up_with_the_influx_of_videos_about_heavily/

Original credit to /u/hoyarugby on reddit

For people who are actually interested in how this developed rather than flogging a particular political horse

Kensington is a neighborhood in North Philadelphia. It's located not too far from the major highway I-95, and is also well-served by public transit via the Market-Frankford Line (commonly called the El, the elevated train above this street)

It was originally a neighborhood inhabited by Eastern European immigrants, who worked in garment factories, making things like stockings and hats - the textile industry was a key part of Philadelphia's industrial economy

The textile industry was one of the earliest hit with deindustrialization - factories moved to the cheaper and non-unionized American South, and then overseas, and Kensington was hit very hard by this de-industrialization. White Flight wasn't as bad here as in many other cities - Port Richmond, a neighborhood right next to this, is still largely white working class - but much of the white population fled and were replaced by Black migrants from the Jim Crow south, as well as hispanic immigrants

By the 60s the area had a large number of abandoned buildings, and the drug problem began then. First heroin in the 60s, then meth in the 70s, then crack and cocaine in the 80s and 90s. The neighborhood became a bit of a drug "emporium" because of its location - it's right near major highways and train routes, so it was a common place for people from outside of Philadelphia itself to go buy drugs. And all of the abandoned buildings created ideal places for people to squat in and do drugs

But though the area was awash in drugs and drug addicts, the abandoned buildings paradoxically helped keep the problems less visible. Large drug/homeless camps were established in abandoned lots and other marginal space - drug addicts and the homeless congregated there

The current situation in Kensington is caused by two things - fentanyl and cleanup efforts

I probably don't need to elaborate too much here, but the opioid epidemic and the influx of cheap fentanyl from China has turned the existing drug issue into an epidemic. Kensington is the place where you can get the most potent heroin on the east coast, for the cheapest price. It's a place that draws in drug addicts, keeps them ensnared, and kills them via overdoses. And it's the most potent of its kind in the country

Paradoxically, cleanup efforts pushed the problem from being somewhat invisible to being out in the open. In general, both the City of Philadelphia, and real estate money, have made an effort to buy up and restore/rebuild many buildings in the area. Kensington has excellent transit access to Center City, and is very close to the hottest real estate market in the city, the neighborhoods of Fishtown and Northern Liberties. Many of the buildings and abandoned lots that served as drug squats and homeless camps were bought up and torn down or restored, with the hopes that in a few years, Kensington will be the next hot real estate market in the city

The proximate problem that led to the current crisis was the clearing of a number of homeless camps, particularly the biggest one in the city, El Campamento which was established in the CSX railroad cut to the West of Kensington. After mounting complaints from neighbors and community leaders, CSX and the city finally cleared out the homeless camp. They were able to get some people housed and/or in treatment, but many addicts refused treatment/housing, and the drug problem will always create more homeless addicts. But now these homeless addicts didn't have an established camp to go to, so instead they just started living close to the drugs - right under the El on Kensington Ave, which is what you're seeing in this video. Basically, cleanup efforts pushed the homeless addicts out of camps where they were mostly out of sight, and into streets where they were very visible

The problem is really bad, as you can see, but there's no obvious thing for the city to do. A charity tried to set up a safe injection site nearby, but both the Trump administration and locals blocked it from being established. The city's homeless infrastructure isn't really equipped to handle the numbers of people here - and even if it had the money, most of the homeless are addicts and will refuse to live in homeless housing that requires sobriety. Kensington is going to remain a convenient place to buy drugs no matter what thanks to its great transit links. And the opioid epidemic will continue to produce new addicts that will be ensnared by places like Kensington

Some articles:

https://www.inquirer.com/philly/news/kensington-opioid-crisis-history-philly-heroin-20180123.html

https://www.nytimes.com/2018/10/10/magazine/kensington-heroin-opioid-philadelphia.html

https://thephiladelphiacitizen.org/citizen-of-the-week-charito-morales/