Trump has a lot of large donors, including billionaires, supporting him as well. Also such deep-state, establishment organizations as Disney, Black Rock, etc. So Neither Trump nor his supporters have any room to look down on Desantis getting support from billionaires...
Those rich Trump supporters are his friends for long time.
Where as Mr. Career politician DeSantis has all new rich friends who were hurt by Tariffs Trump imposed on China and are pulling strings of puppet RDS.
If there is one thing Trump did during his 4 years was to do MAGA initiatives and not help his rich friends.