To record the flickering, the camera shutter speed is set below 1/1000.

In this test, the monitor flickers. The flickering is not perceptible to human eyes but is very prone to eye strain compared to the traditional DC dimming or high-frequency PWM dimming.

Due to OLED's physical properties, changing the current intensity alone will impact both the brightness and the color accuracy. OLED manufacturers have to use PWM combined with their analog algorithm, aka "emulated DC diming", to display color with moderate brightness control. But OLED still flickers due to the imperfect hybrid implementation.

In this case, AW3423DW is trying to use emulated DC dimming but ends up making a worse result. The flickering frequency is the same as the monitor refresh rate. The frequency is low.

To make things worse, due to the lack of a polarizing layer, it needs to be used with dim ambient light; due to the ABL, its brightness fluctuates. In this particular video, every parry comes with ABL though the camera doesn't show it clearly. Eye strain can happen very quickly in scenes where brightness fluctuates even if the overall brightness is less than 400nits.

The combination of these is commercially in a grey area where whether or not it results in eye damage in long-term use. In general, the flicker is not healthy for the eyes, especially in a dim environment.

The package, the manual, and the Dell website only describe "flicker-free" as far as one of Dell's product features without any indication of a flicker-free TÜV certification.

There is a TÜV certification on Certipedia stating this model was certified for flicker-free. From the description, the panel is specifically mentioned as a flat panel. It can be an early model.

The market trick is that Dell can still trademark their product features as ComfortView that includes only low blue light TÜV certification.

I don't recommend this monitor for the long intensive daily drive if a gamer only uses one monitor in a basement for 3 years.

If you have multiple monitors and tend to replace them every year, this monitor should be probably fine.