The thing is they probably don’t care as you are probably not their target customer. Client-side blocking is probably good enough for a business reader looking for tech insights that might very well decide “screw this I’ll subscribe”.
FWIW turning off javascript has allowed me to read HBR for more than a year so far. I bet they don’t care...
I achieve the same thing simply by opening the site in incognito window. Too bad I cannot write a blog post about it.