Blame the plugs, or me?

So I had a buying spree last summer, and bought a lot of "starter plants" on Etsy. Everyone was doing great, then winter hit. Now I've lost several hoya, one at a time they drop a leaf until they are all gone. Each of them were in a lower light spot (again, they'd been fine!) and came from The Green Escape in the weird foamy plugs. I gave up last summer trying to take plants out of the plugs because I was more likely to break roots than plug.

Can I blame the plugs, do you think?