For anyone doing color critical work a $100 calibrator should be a desk accessory.
Even the factory calibration on every single Mac in my house (there are several, including a brand new M1 Air) has been notably off until calibrated.
The unfortunate thing about the iPads is that though they cover the DCI-P3 space there is no way to calibrate them. My Pro is significantly off my calibrated iMac and Air.
I'm not sure what consumer monitors you're using, but they are certainly not "extremely off". You're making it sound like shades of green on the iPad turn into muddy brown on a monitor, which isn't true.
I had the ipad connected to a $700 LG monitor and the LG one was much much redder than the ipad, the difference was significant. It's fine for programming, gaming, and content consumption, but if you were doing any visual production work, this is unusable.
So calibrate your LG. (something you can't do on your iPad).
> "but if you were doing any visual production work..."
...then you would press the menu button on your monitor and adjust so that your monitor is usable. The default settings on your LG do not represent every monitor out there. A lot of monitors have good out-of-box colour.
> $700 LG
The monitor market is competitive. Watch reviews and choose a monitor with good out-of-box colour if you can't be bothered calibrating. Something like the ASUS Proart, or numerous others.
What does being off mean? If that's how everyone sees it, isn't that what you should use as reference instead of a device with "correct" rendering that only a few people uses?
Each screen is off in some way but not the same way. By grading on a screen that is properly color graded you prevent the picture from looking trash on some. Imagine color being off is a vector in 2D space starting from origin. It can be in any direction. If your monitor is off too then your color error vector would be added to the consumer's color error vector. It might make the color even better for some when those two vectors cancel each other but make it outright unbearable for other's. That's my understanding of it and not very accurate.
Being “off” means that what the monitor emits is not exactly what it should have been. Too bright, too dark, too red, too whatever. There is no one “off”, every display is differently incorrect, so it would be impossible to use as a reference. The correct reference is a sufficiently accurate representation what every display aims to be, even if they don’t quite get there. That’s what calibration does: get closer to the target all displays are trying to achieve.
