Be weary of generalizations. If you say all immigrants are incapable of integration, that could be a prejudicial or biased. Also, it is not a truthful statement.
Asking questions such as 'What is bias', 'what is prejudice' and 'what does the lack of integration do to hurt society? Seeking answers like this is a healthy pursuit.
On the surface, it is not a racist comment. Is the effect of immigrants not integrating hurting another group or is it discriminatory or illegal?
Is the plight of an immigrant group due to their lack of integration, a voluntary act or do they have no choice?
If some immigrants chose to not integrate might be considered a fact and an observation of behavior. However, if you or anyone else, declares that all immigrants can not be integrated, that would indicate a bias or a prejudice. However, also...aren't you STILL confusing bias and prejudice with racism? They are not the same thing. There is no indication to what you're asking that indicates someone is stating they're superior. Indicating a preference is not necessarily racism.
For something to be called racism and be considered as discrimination depends on what details exist to back it up. And it depends on what sort of generalizations the person makes ...and whether or not the person's behavior is one where they're casting aspersions on another group and discriminating against another person or group and getting an advantage ..financially ..say on housing.. or jobs, etc.
For example in Little Havana in Miami, there are Cuban-Americans that speak very little English, preferring their home language and they shop in the Cuban community. They may choose to not integrate ..out of choice to support their community, but they are not creating an atmosphere of racism. They do not prevent the laws of the land from being observed or enforced.