Well that's a firm but fair predicament you have there, but as i've mentioned between the apprentice & the shop owner, there is critical differences for the same job. The apprentice will learn and eventually take over the shop on the basis of 3 primary conditions
- The owner dies/is murdered and with no next of kin the shop now belongs to the apprentice
- The apprentice surpasses the shop owner in skill, causing them to retire - The intended course of action for cycling through master and apprentices imparting experience
- The apprentice obtains the shop via another means such as buying the property
Your ability or circumstances translates directly into success given that in this dwarf physics world if you are marginally bad at a job you perform it poorer and hence the most competent traders earn the most personal wealth, handled in worldgen via local currency and powerful nobles people talk about swaggering around with gold in their pockets.
There's some other things too like personality to take into account, but as the responsiblities change as they gain a new noble status via appointment or just self-development and ambition, the existing set of skills and personality faucets affect negatively or positively, given that a merchantile duke with no respect for the law known to hire brigands and lie would not make a good king.
There's not such pieces of the puzzle implemented yet such as inhereting land or properties, but as of the next version you can inherit family artifacts or actively depending on your status pursue said artifacts from the clutches of others, hence what might prop up a noblepersons position in one kingdom, when it is reclaimed by its rightful owners they might go back to being a lowly humiliated peasant again because of a substantial loss of wealth or even go beserk depending on their personality.
People from rich families often pursuing careers that suit them to stay rich, most certainly you've never heard of anybody in the peasantry even being notable unless they've successfully been the leader of a hamlet for a number of years or were popular enough to be elected the mayor in a small town settlement.
Id say it applies much more to humans than dwarves, but id rule guilds in as a exception given that you must be competent & have a set of skills to proceed within unionistic politics and grow substantially powerful enough to front a guild or form your own. And from there you're powerful enough to lock horns with other guild members and even bodies of government over whatever matter is relevant.
Yeah you're right to point out how feudal goverments basically used fiefdoms as rewards, its a give a man a fish it'll feed him for a day, give a man a fishing lodge and it'll feed him for a lifetime and you might get some out of it too. Easiest way to elevate any notable peasant up to someone of meager importance and work from there by basically raising the value of the things they own by a substantial amount.
Unless the land is ravaged with misfortune and war, hopefully the current lawgiver's won't end up being as poor as that example but just hold onto their seat purely by the will of monarchic inheritance between their relatives.