Is Madrid's Mbappé Law really worth it?

There has been a lot of talk about Madrid's new controversial Mbappé Law, but will it really be worthwhile and how much can you actually deduct from your income tax?

Is Madrid's Mbappé Law really worth it?
There has been a lot of talk about Madrid's new controversial Mbappé Law, but will it really be worthwhile and how much can you actually deduct from your income tax?