While I agree with the general sentiment, I would not classify Dolby as a "patent troll" — they still do invest in research and developing products, right?

I'd classify any patent racketeer as a troll. Dolby has nothing to do with AV1, they just want a parasitic rent on it. Whether the troll actually does anything else besides the trolling part isn't really relevant.

Patent mob seems more fitting.

Another example is Qualcomm

How is Dolby a patent troll? :D

Because they have nothing to do with AV1, they simply want to leech on it. It's fitting to call them a patent troll.

they're a company that doesn't make any products. they just get actual hardware engineers to pay them to put a logo on their devices and to prevent Dolby from suing