i dont run one of said shops, but have helped a lot of customers make that switch over the years - usually licensing being cheaper was a huge driver, and the other components included with the suite that these shops were paying others for that they could stop (i.e. appsense, flexapp, etc. ) ... feature wise there's very little difference at this point unless you start looking at some of the more niche features that have been included in citrix over the years that Customer X's team may be used to using.. and in that case there's usually some other way to accomplish whatever "it" is
i will say that citrix generally has a little better management of published apps in the RDSH sense of things, like the ability for a user to reset their session if it gets hung, some of the load balancing, etc. -- but most of the apps that i've seen on takeouts have ended up just being converted to App Volumes because the only reason they were ever published in the first place was to limit who could use it w/out installing everywhere and/or doing funky permissioning.