What are the experiences of transitioning from a Work Permit to a Digital Nomad Visa in Thailand?

As others have said, you didn't explain what documents you submitted so we can't tell. Did you submit things like tax returns, transaction history, performance history, monthly statements, or did you only give a list of holdings? How many years did you provide? How did you explain activity like how much work you do with managing the portfolio? And how you do it? Did you tell them how long you have been doing it? Did you tell them why you are going and what you're planning to do? And how much income do you actually make from the activity, is it as much as someone with employment? If you got lucky for one or two years that doesn't really demonstrate a history of sufficient regular income. Did you tell them that it was your own account and assets so that there was no business registration or contracts with third parties, meaning you're not providing services to third parties? And which embassy was it?

Do the Elite Visa. You quality for that $$$. DTV is not allowed for investors. It is for self employed with a registered company, proving your business & client affairs, or working for online for company.