Should I work at Tesla/SpaceX or Microsoft/Google?

I'm a new grad who some experience with both low level software and some backend systems. I have to choose between Tesla/SpaceX and Microsoft/Google (one of each) and I'm really torn. I lack the wisdom to understand the long term implications of my choice, and both seem really great. On one hand, Tesla/SpaceX are growing rapidly and changing the world. Meanwhile, Microsoft/Google have talented engineers and great culture with excellent pay, perks, and benefits as well as a strong learning environment and a manageable workload. Additionally, Microsoft/Google translate well into other job opportunities down the road, as their brands are very strong and their engineers are known to be very capable. I feel that Tesla/SpaceX aren't as software focused (Google basically wrote the book on modern day distributed computing), so I'm worried that, while I'll have more responsibility and impactful work here, I may not be as strong technically in the future. However, I feel that I'm underestimating the benefits of the growth that Tesla/SpaceX are experiencing. I'm afraid of missing out on great opportunities that these companies can offer. What does HN think about this choice? What would you do?