Heck, the Javanese language (spoken by a huge fraction of Indonesian) has 3 sub languages depending who you’re talking with (your friend, your parents, or a person with much higher social standing than you). To outsiders, that’s effectively 3 languages you’ll have to cream into your head (because the sub languages have different set of vocabularies), while the native themselves consider it one language.
Heck, the Javanese language (spoken by a huge fraction of Indonesian) has 3 sub languages depending who you’re talking with (your friend, your parents, or a person with much higher social standing than you). To outsiders, that’s effectively 3 languages you’ll have to cream into your head (because the sub languages have different set of vocabularies), while the native themselves consider it one language.