I have friends who say warsh as in warsh the clothes. Their families are from Ohio, but the majority of my Ohio friends say it correctly.
My mom adds an r to the end of words ending in a. Classic Bronx, NY. Idear instead of idea. Words that end in r she leaves it off sometimes. The stove burner she would pronounce more like burnah. Hers isn’t extremely exaggerated, but she never really lost it even living outside of the Bronx for years.
My husband still sometimes says yellow like jello. Mexican thing. Y’s sound more like J’s in Spanish in Mexico, but he can say it correctly.
Some sounds are extremely difficult to learn as an adult. If you live in a community of people who immigrated here, and everyone around speaks English in that accent or dialect, it might influence how you speak. Children born in America who are surrounded by “American” accents learn that accent usually, and not the old world accent. Even if the community is very diverse. If the community is full of people from one country, then that often does have influence.
Then there are countries that simply do not teach the correct sound. For whatever reason Japan teaches L to sound like R.