That’s what I’ve heard as well. The producers made a conscious decision to not worry about language barriers, unless said language barriers were a plot point.
A few more: in the movie Daniel’s future wife is Sha’uri and pronounced “shah-uri”. In the TV show she is Sha’re and it’s pronounced “shahray”.
In the movie he’s Jack O’Neil. In the show he’s Jack O’Neill. This is lampshaded by the character saying it’s spelt with two L’s, not like the “other Colonel, that guy has no sense of humor.”
At first Teal’c is “from Chulak”. Later he’s from a city called Chulak on some planet.
It could have been a close female cousin or friend..
(I’m not arguing that it is not, in fact a continuity error, & fully realize that I’ve spent too much time thinking about this)
My opinion is that each season of MAS*H exists within its own universe. That’s the only way to explain all the holiday episodes and the fact that one episode had Col. Potter there for the entirety of 1951 when his introduction said he arrived in '52.
Krusty did try to learn to read. But they varied in how well that went. The most glaring break was in an episode where they show an old black and white Krusty clip where he reads an important news bulletin live on the air. How could the son of a Rabbi who could read Hebrew as a child not know how to read English? (Brain damage from ???)
But this is a show where the family meet both then First Lady Barbara Bush (in the White House bathtub!) and current First Lady Michelle Obama without anyone getting older. In flashbacks, teenager Homer was too busy listening to music to pay attention to the moon landing and was a toddler at Woodstock the next month. Etc.
The Simpsons uses a Marvel Universe style floating timeline. Homer is always 40ish in the present day, which means in flashbacks he is continually moving forward in time. The last big Homer flashing back as a young adult episode had Marge and Homer living in the 90s (“That 90’s Show”).
For a great story about the “Floating timeline” check out Kim Newman’s story “Coastal City” available on his website Coastal City | The Kim Newman Web Site