I’m guessing that some people who have accents, especially French and British, would not want to change their accents, especially if they moved to the United States, because their beautiful accents make then sound unique and us American’s love those accents.
On the other hand, I worked with a lot of folks who came from the Philippines and they had all been in the U.S. for at least ten years or more, some of them for 30 years or more and they all had very thick accents. I think that was because, outside of work, they didn’t generally socialize or come into contact with American born, English speakers very much, because there is a large Filipino community in our town, and they live there and don’t speak English at home. They speak Tagalog. They all spoke English well enough to get by in an English speaking job, but there was no need for them to finesse their accents.
With regards to cursive, some people are just better at it than others. There may be a higher percentage of females, for whatever evolutionary reason, that are better at it than the guys.
Although I studied hard with mathematics all through grade school and then on into college, I have always struggled and have never been good at it. I actually hate math because it was always a miserable struggle for me. I spent hours and hours trying to get it, but I just don’t have the capacity. Other friends of mine came to it naturally and really never had to work at it to be good at it.