In fact, sociolinguists are far from unanimous about the fate of languages; with enough willpower and cultural attachment, minority/underused languages can flourish, witness the renaissance of modern Hebrew as a national language and the push for a renewed Irish language in the public square; 
as the great historian Toynbee said, he didn't how History would end, but he did know that at the end  the Chinese and the French Canadians will be there. Resilience counts.