I don't know what the law says about remote work in the EU, but for Americans, this is 100% unadulterated bullshit.
Terrible legal advice. Remote work does NOT automatically make you a contractor rather than an employee.
Indeed, lots of people are normal employees, but not in a central office.
On almost all other points he seemed incorrect for most of the jurisdictions I've worked in. I'm sure some of it is true for some jurisdictions, but way overgeneralised.