No, I think it's a disadvantage in the international workplace, or will be if we allow it to in the future.
Comparing myself to the average German student I've met on my Year Abroad, their English is as good as my German. Yes, there are a few who can barely speak it, but most are very proficient.
Comparing myself to the other international students I met on my Year Abroad, their English is as good as or better than my German, many of them were perfectly fluent, and if not, they were at least good at another "foreign" language as well: German.
When it comes to applying for jobs, who will look more attractive to an employer? Your average Brit with a GCSE in a language, maybe an A-level if you're lucky, or a native speaker from that country with excellent English skills?
In the unlikely event that I have children, no matter how good their natural ability at learning languages, I am going to make sure that they learn at least one, preferably two foreign languages, and can speak and write them at a good standard.