My current setup is Fold4 with BT keyboard and mouse. This is what I use instead of laptop for work when traveling. It's not perfect but more capable than expected. DeX is surprisingly usable but mobile applications lack in some areas. Luckily most of my work is around code so getting Termux solves most of the issues. S7 Galaxy Tab should have pretty capable DeX implementation which doesn't require external screen to work. For me just foldable screen is good enough for writing code.