@NamedUser Afaik the problem is more about ‘desktop size’ combo amps: the kind that follow the Yamaha THR form factor with 4-6” speakers, calibrated to sound good even at low volume, almost never have fx loops. There are plenty of ‘practice’ combos in the same price range with effects loops but they tend to have 10”+ speakers. (The bigger size Boss Katana, Orange Crush, Line 6, Fender (etc etc).) And those larger speaker combos are rarely calibrated/designed to sound great at truly low volumes.
Part of the issue is that the selling point of those quiet desktop amps over a custom chain that ends with studio monitors and/or headphones is plug and play simplicity. For users that are committed to using a setup with their own fx loop chains, there just isn’t as much obvious upside to these ‘desktop practice amps’ over sticking a modeler in your effects chain, and playing through studio monitors or headphones…