let's assume any custom/belief can be had, as long as it does not violate the rights or customs of another person. peachy right? political correctness circumvents this by expecting change on one or both parties.
party (A) changing custom so as not to offend party (B) is, like it or not, indirect oppression from party (B).
for happiness on both sides, the only required variable is "respect". and respect dictates that nothing must change. this is not however the be all and end all, respect does already protect the groups who were supposed to benefit and be protected with political correctness. originally it came about for women's rights, anti-racism and other noble causes.