For me the PC is a tool as well. However, my tasks are somewhat different. As a couple of examples, sometimes I'm doing calculations taking 100% CPU resources and sometimes I make presentations with a laptop. In both cases it's very important that the OS does not do anything else, but the task I set it to do. That means no updating, maintenance, scans, etc.
Unfortunately I see very often that people come onstage to give their talk only to see the message from Windows that a reboot is necessary or an update is important. Somehow, Windows does not understand that if the user is making a presentation, no extra information is needed onscreen right at that moment.
One other thing Windows completely fails at is the concept of the PC being idle. If I set the machine up for a heavy calculation and leave it to work for a couple of days, it's not idle, it's calculating. However, Windows defines "idle" as "no user interaction", meaning no input from the keyboard or mouse. This is completely ridiculous. If I use the machine for computation, I very often do not touch it until the calculation is finished, which may take days. However by default Windows will interfere with all kinds of automated tasks and ever will go to sleep if I do not move the mouse every half hour or so.
So from this you can guess what "tinkering" I'm doing. It has nothing to do with how the GUI looks like. What I do with the OS is to very carefully examine all automated tasks that may run at random time points and either reschedule them or turn off the automation (e.g. I do not need the OS to do any automated defragmentation while the machine is calculating, so I turn off automated defrag task, etc.). Similarly, automatic Windows updates are turned off - I check for updates manually. Windows Defender is off - I use another security suite (ESET). And so on, so forth. All in all, I need to go through Tasks, Group Policy, Services, Updates, and so on. It takes a while to set it all up. Windows Updates that introduce extra telemetry do not help, but since I do not install any updates automatically and always check what each updates does before installing, I manage to avoid all that stuff (e.g., I never had GWX installed and so it does not bother me, no Windows 10 files downloading automatically, etc.)