maybe you are referring to this? this will move as slow as the fastest glacier in global warming 

https://www.lightcounting.com/newsletter/december-2021-the-right-path-to-16t-pam4-optics-8x200g-or-16x100g-227

We suspect that Amazon have encouraged these vendors to come up with a lower risk and faster path to market for 1.6T Ethernet transceivers

.....

Several suppliers recently demonstrated the feasibility of 200G per lane optics, but the potential customers are concerned:

Can suppliers manufacture 200G optics with the high yields needed to reduce cost?

Will it be as reliable as 100G optics and how long will it take to qualify these new chips?

....

If 4x400G modules make it to the market, we will have three generations of 1.6T transceivers:

4x400G: 16 lanes of 100G on the electrical and optical sides (Gen zero?)

8X200G Gen-1: 16 of 100G electrical lanes and 8 lanes of 200G optics

8x200G Gen-2: 8 lanes of 200G on the electrical and optical sides

Gen-2 will need 200G SerDes, which is another high-risk new technology, which will not be available until 2025. The sweet spot for Gen Zero is 2023-2024, Gen-1 2025-2026, Gen-2 2027 and beyond.