What you were asking for in the "If I were a manager" part is in fact a thin client, and they were made quite for the reasons you named. Beside the huge mainframes and TTY terminals of the stone ages, in relatively recent past there was a very solid platform called Sun Ray as a terminal able to display X11 sessions from a Linux or Solaris server (and related to it, originally Tarantella's Sun Global Desktop for the browser-based remote desktop/app access, and later Sun VDI for dynamic per-employee VMs). The benefit here was that the "Desktop Terminal Unit" had no mechanical parts and no brains, it was on your desk for 10-15 years and as servers and technological abilities (X11, browser, vdi, ...) behind it were upgraded your desktop unit never had to change. And if some condensor did die, you just picked another DTU from the closet and plugged it in, and the user with their smartcard had their same session continued instantly. 81
With about 400Kb(!) of firmware making it a remote video/keyboard/usb connection it virtually had no attack surface (marketing boasted just 4 issues found over almost 20 years on the market, 2 of which were found internally and never reached the open market), and had a good seating in companies, banks, military... until literally one day an Oracle exec said they disband the project, ciao to the team.
A modern equivalent is a small terminal computer with minimized Linux or similar distro, though not in Sun Rays' range of lack of attack surface, but also offloading (much of) computation and data to the secure central servers. Being a computer, they are more capable than Sun Rays for the modern office needs, from the useless video effects of transparent menus and window shadows, to the more useful video, VoIP etc. support and/or acceleration where supported by respective remote-desktop protocols.
I did not watch this area lately, so can't recommend what is good today. However, at the time of Sun Rays' untimely demise, many community members discussed migration to ThinLinc as their top choice; I'd assume this influx of geeks and ideas and battle-proven expectations could improve that ecosystem. 81