HDMI 2.0b not support 4k@60Hz with 30 bits 4:4:4 (lossless). But DP1.2 (from 2009 year!) is support this mode (but not support HDR protocol, it support DP1.4+ with max 25.9Gbps user data). HDMI 2.1 support 4k@120-165Hz with 30 bits 4:4:4 (lossless) only with full bandwidth 48Gbps (with service+user data and max 42Gbps with only user data).
DP 2.0 (full version) not support 8k for 100Hz+ even in legacy 24-bit color depth.
As we already know in advance, DP2.1 does not increase the bandwidth to the required 160Gbps in any way. In any case, as I wrote earlier - copper is no longer suitable for such a bandwidth - we need optics that solve many problems at once. Why it takes so long to implement this, I don't know.
In any case, 8k resolution is currently only possible in 2D and light 3D. Those. about games in 8k in the next 10 years there is definitely no question. Basically, 8k finally closes the topic of increased pixelation of fonts on screens of 25-32". Exactly where 4k is no longer enough (even at 25" 6k is already required at least to provide sufficient ppi around 270+).
Actually, 8k closes the topic of super-clear fonts, vector graphics and photos on the most popular diagonals for business and study. That is why 8k is so important. This is a new milestone in the history of information display, about the same level as the appearance of the first laser printers with at least 300 dpi.
It is unfortunate that Moore's "law" has practically stopped since the 2010s precisely because of the lack of sufficient bandwidth, interfaces and processing power of processors, we have remained so with the introduction of 8k in everyday life and business. At least 5-6 years. The 8k panels themselves physically appeared in 2013.