This probably will end up in a new thread…
I am not aware of any cloud system that doesn’t have a similar gateway binary: Azure Arc, AD Connect, SQL Connect, Azure DevOps or GitHub Actions local Runners, etc. It’s inevitable. 
I think the main complaint is the difference between having the gateway at servers or specific workstations (for labels or scales) vs. being distributed to every single workstation. Of course, this is context dependent. If users want to continue to use local network shares, then this is a legitimate price to pay for that capability. Using the EC for browser first until the classic client is no longer used, is again an excellent, time-limited application.
Before Stephen Edginton left, there was talk of utilizing web workers to do some of this kind of work. This would simplify the management of the code as web workers run even when the web application is not open. It might be a good candidate for the System Monitor for example. Printing could use a server-based gateway much the same way that BarTender can. The Web Serial API can work with Web Workers too.
And separately, QZ Tray runs under Java, so each workstation that installs it takes on that extra security dependency. So, I don’t blame some administrators for trying to avoid the EC when possible, as living off the land vulnerabilities are harder to prevent and detect.