I know that it is illegal to work in Thailand while on a tourist or retirement visa, the Philippines has the same rule.

But in the Philippines, if I understand it correctly, they have an exception - you are allowed to work online teaching English, like teaching people in Korea English, or doing online marketing for a Western country, as long as the money you make goes into the country, and not out. Does Thailand make that same exception?

No and working on retirement is not forbidden - but normally a work permit will not be issued and work without that is.

As a retiree there is no law that you can not invest in a business and get income. from shares. My wife owned a farm and I helped her. Many government an officials visited our farm as well as forestry people. They all saw me working. No problems.

As long as nobody reports you to the Department of Labour you may be able to continue to fly below the radar. I suggest that in the meantime you do no proclaim that your are working without a work permit, treat "work" as a dirty word (it is a four-letter word, after all); you are living happily with your Thai wife, pursuing one hobby or another, going for leisurely walks on your wife's property, etc. You get the drift.