What are assumptions based on which Solana achieves 50 K TPS?

Solana advertises that it can achieve 50K TPS. But most of the times the network only get 2500 TPS.
What are all the assumptions that need to be satisfied to actually achieve the 50K throughput securely?
Eg: What are the assumptions on number of validators, storage requirements, computational power, number of cores, number of GPUs, bandwidth, physical distance between validators, number of hash computations per sec, etc?

I see validator requirements in Solana docs. But from that, I couldn’t directly deduce that Solana could actually achieve 50K TPS.