Most people only notice flicker during saccades. A larger proportion of people will notice scrolling purple/blue smear, that manifests itself at extremely low source current, when you have really dark shades of grey on a dimmed screen in low brightness environments.
As an aside, burn-in and mura seem to be solved problem these days, due to display driver ICs constantly characterizing the I-V curve of individual subpixels and applying compensation using aging models. Variabilities introduced during manufacturing are also optically captured for compensation.
Additionally, there exists compensation circuits within the TFT plane for fine-adjustement of uniformity for each subpixel.
MicroLEDs are not magically immune to the issues affecting OLED. https://www.oled-info.com/measuring-and-correcting-microled-...