It would be great for TP-Link to come out with a smart plug with dimming options for plug-in lamps. I exclusively use TP-Link smart plugs for all of the lamps in my house and having this feature would be great for some areas (e.g. Living room lamps). There aren't a lot of good options out there for wifi dimmable smart plugs and I am sure that TP-Link would make a competitive product which could function well. Also, many LED light bulbs are dimmable at this point.
And in response to this thread (https://community.tp-link.com/us/home/forum/topic/175022), I do not think having a smart plug is a "niche" market at this point. There are some major players who make this type of product at this point, including but not limited to Lutron Caseta, GE, Honeywell, Legrand, Insteon, and any number of cheap chinese knock-offs on Amazon. If certain products like Lutron didn't require me to buy a hub to function with smart home assistants and I had more of their products installed in my household, I would probably just end up buying their options.