These numbers are made up. Forbes's lists of "richest" or "wealthiest" are a joke and made up numbers. The lists are 99% made up because nobody actually provides their personal information to some reporter. Endorsements companies don't give details of contracts. Unless the information is required to be publicly disclosed, I can guarantee you they're made up. Big numbers are used for page views and clicks, or the athletes' agents leak made up numbers to make their athlete seem more important.
The only thing we know for sure is the prize money from the competitions. Grand Prix Individual Event winners get $18K, Final's get $25K, Europeans or 4CC get $20K, World's get $45K. Assuming you win 2 ISU event's, GPF, Europeans, and World's that's only $126K. After the Russian Fed takes their cut(15-20%) and the coach or coaching team takes their cut(20-30%), you're probably left with well under $100K. That's only if you win 2nd and 3rd place make considerably less.
The next issue is skating show money. Japan is the only place where skaters can make decent money. Alina spent her summer in Japan, not Russia. The skating shows in the USA were mostly empty according to the internet. If the average Russian salary is $600/month, that doesn't leave a lot of money to attend skating shows.
Gate revenue at skating events in non-Japanese locations is probably minimal. Even if the stadiums were are reasonably full, there are only 6 grand prix events worldwide. Most of my high school hockey games were better attended then some of the events, and we played a lot more games.
Attendance is one thing and TV viewership is the other. Companies don't pay to be corporate sponsors unless they can get viewers. Most of the people on this forum watch videos from illegally uploaded Youtube sources.
Hanyu is an economy by himself. You can't use him as an example as he is the only superstar in skating. That was one event in Moscow, the wealthiest and most populous city in Russia. It was obvious the crowd was full of Japanese fans. It's night and day between attendance of Yuzuru and non-Yuzuru events. His fans and only his fans travel well across the globe. Nathan Chen beat Yuzuru at World's. The event was blip in the US sport's news cycle.