Any popular language can be useful. It depends on your future job plans. If you expect to work internationally, Russian won't hurt. Of course, learning Chinese can be a smarter investment in today's world.
I was also unsure before choosing to study Russian at university, (especially as it would mean giving up 8 years of French.) Looking back, I don't regret anything. Russian is in demand in many sectors, ut even if you ultimately don't use Russian directly in your future career, it still impresses plenty of potential employers. It is a talking point in interviews: It shows that you have the dedication to learn a more challenging language, and the bravery and tenacity to try something new. As as English-speaker, it was more difficult to pick up that a Romance language- but if you enjoy a challenge, you'll find Russian very rewarding.