I am doing all my radio amateur activities according to Czech laws and rules issued by the Czech Telecommunication Office (https://www.ctu.eu/). To date, there is no law or rule assigning the status of a "pirate" or "illegal" to D1 stations. Therefore I deduce that these stations can participate in the MWC and I can accept their logs.
I think Alexander, D1M is not responsible for the current state of the territory in which he lives. I'm afraid he is not allowed to use the standard Ukrainian call sign and the D1M is the only possibility for him how to remain a radio amateur.
I would like to remind that our country, the former Czechoslovakia, was occupied by the Soviet Union (with the help of four other countries) from 1968 to 1989, and then no one in the world took OK stations as "pirates" or "illegal".
After all, if I'd took a discriminatory view of D1 stations, what should I do with stations operating from the occupied Crimea? I really do not want to pull politics into the amateur radio.
73 Julda, OK1NE