Help with Polish ancestors names - Jagiello

Hello
I am wondering if anyone here has any info on lineage to the king (władysław Jagiełło). Does anyone know what happened to the family after the dynasty ended in around 1570-1600? I am told that the name Jagiello was not allowed to be adopted until after world war 1 or 2 so anyone who carrierd the name in this orginal form prior to early 1900s would be some type of descendant...

I doubt that you're descended from Władysław Jagiełło.

I doubt it, too. The dynasty died out, yet my plumber's surname was Jagiełło. Very strange.

If there are people or families with the name Jagiello, their connection to the king is based on similarity not familiarity.

Then you suggest that my plumber looked similar to king Jagiełło? Indeed, he looked a bit like Jagiełło on this famous portrait of the king by Jan Matejko ...

Yes I thought perhaps it has died out too I believe Anna was last relative around late 1500s.
And if the plumber nameay have been adopted/ modified in 1900s. In the US when people came over many times their names would be changed or modified. I'm saying anyone carrying the name prior to 1900s its very strange because it is known that you could not change your name to that of the royal family until the 1900s when Poland was reinspring nationalism. We have to use some logic here. Poland was not even a country in the 1700s -early 1900s. There is no way anyone would be able to use one of the Royal family names as its a sign of nationalism. Secondly how the heck would an ancestor from 1500-1600s be able to use the name of the Royal family if they are not affiliated with the family! Makes no sense.