☆ If SpaceX "Starlink" wants to utilize Boost Mobile they (Must) obtain permission from both AT&T, and T-Mobile; who (Currently) provides their Wireless Carrier Network services.
■ Even if Musk purchases Boost Mobile, he would still need to build his own Wireless Carrier Network for his SpaceX "Starlink" services.
■ Which could take 5-7 years, and $500.0+ Billion; to do so (with High Inflation costs for Raw materials).
■ Boost Mobile is essentially a Cellular service (Reseller) without their own Wireless Carrier Network (like most, except for AT&T, Verizon; and T-Mobile).