Yes, I know and like the ESP32, I have a drawer with different flavors of ESP32 and the older 8266.
But surprisingly, it turns out I didn't used it a lot so far in practical projects, it's often overkill and it lacks i/os.
I also have a 16 i/o board to be connected in i2c with and ESP32, but not used it in a project yet.
No actually, most of my projects, I use a good old Arduino Nano, it fits a lot of situations. Or I tend to use now the Arduino micro, because of its usb support, and it's ability to be seen as a keyboard or mouse.
I will have to show also my CNC pendant, based on micro, which sends key stocks to Mach3 or SimCNC (the new soft I used from Cslab now)

About Mach3 being interrupted by Windows, I'm afraid you may see them happening when you won't think about it.
Same as you, my shop PC has no internet access, and I try to disable whatever I can, and until recently, I did not notice any trouble (it's running W10 64bits)
But, I decided to upgrade it for good measure, and to speedup its boot time and responsiveness, so I changed the HDD to a SSD.
Very efficient ! But alas, here came the troubles. I think it is now so fast in disk I/O, compared to what it was, that when Defender passes (and it always passes, sooner or later, even if you have disabled it), it is not self regulated as it naturally was with a slow HDD (meaning the proc mostly waiting for the disk, so letting time for other tasks), now the SSD is more responsve and when Defender loops on some disk resources, it really takes a lot of cpu, and typically Mach3 is disturbed, you get the "hourglass" cursor (sorry I don't know the exact English for that) and it's no more responsive, and the CNC looses steps meanwhile...

So for me, unless you have a modern fast PC with plenty of cores, Linux is far much reliable to run a software that needs somewhat real time responsiveness.
Note that now I have moved to this CSMIO IP/M board with Ethernet connection, I first tried it with Mach3/Windows, because they say with this board, more of the real time stuff is actually executed by the board, with a bigger code buffer, but alas again, when the disturbance occur, I actually loose the Ethernet connection ...
So I decided to get rid of Windows/Mach3, and I'm now happy to be on Linux/SimCNC. (and I gained the laser support)
Well, I will have soon to pay for a new license for SimCNC , I am still on the 3 month free trial license. It's about 250€ I think...