I'm in the same position - The new net filters block PT Community sites, despite how much we pay PTC for all our MCAD and Mathcad tools. The request to unblock is already in! Hopefully next week we'll get access again.
And yes the web experience is very poor, so all the old hands who actually know how to use mathcad, and what it can do, are stepping back, with one or two notable exceptions. [the web experience is very pretty, and modern, with it's invisible (hard to read) greys that all the sites love these days, but it isn't addressing the function that's required]
One of my colleagues on the PTC MCAD/Creo side notes that whenever PTC buys a company it's sucked in, mangled and chewed for 5 years before being spit back out as a new 'PTC' drone (that was for a company that auto converted production drawing to tech manual drawings). Mathcad's going through the same to become an aid to draughting/drawing. It's hard to see if the managers at PTC eve realise the hidden capabilities that are in Mathcad.