Same problem here.
Maybe fixed in v7.18beta2?

*) ethernet - improved link speed reporting on 2.5G-baseT and 10Gbase-T ports;

no
also have this bug

) x86 - fixed "unsupported speed" warning; update 7.18 b2，also have unsupported speed https://forum.mikrotik.com/download/file.php?mode=view&id=71149 https://forum.mikrotik.com/download/file.php?mode=view&id=71150 https://forum.mikrotik.com/download/file.php?mode=view&id=71152 ...

ROS in pve
chr 7.17
interface ether3 is SFP+ , INTEL X710

What happened and how to solve it

sorry，my English is pure，hope someone help me
download/file.php?mode=view&id=71059
download/file.php?mode=view&id=71060