The optical corrector lens -- just the corrector lens alone -- that is part of the camera instrument of OP has a diameter of 1m, with a mass of about 200kg. (https://www.darkenergysurvey.org/the-des-project/instrument/). The entire Starlink satellite mass is 227kg.
I don't think SpaceX is going to be putting instruments of this class on its satellites.
Dedicated CubeSats have largely filled the smallsat niche. I would expect the Starlink mass has been carefully optimized already.
There are interesting mission concepts (telescope + star shade; NEO detection [1]) that are in the works with dedicated CubeSat constellations, but yoking them to another spacecraft bus with its own constraints doesn't sound likely to succeed.
[1] https://www.aanda.org/articles/aa/full_html/2017/07/aa29809-...