Back story behind this decision
At the moment you are only taxed on foreign income that you remit to Thailand during the year that it is earnt.
So for example if I was to earn money in The Gambia in 2022, if I remit that within 2022 then it is taxed. But if I leave it outside the country and remit it in 2023 then it is not taxed.
Essentially they are closing a loop-hole that enabled people to not pay tax on foreign earnings. For example a Hi-So could setup a company overseas, pay themselves a big salary to an offshore account and then only remit that to Thailand 1 year later and pay no tax...