I'm not a doctor, but for what it's worth, it seems like your doctor prescribed drugs that would effectively treat a severe case of covid.

Severe covid causes an overly aggressive immune system response that results in inflammation in your lungs, and even other organs like your heart. Methylprednisolone is a corticosteroid that reduces inflammation. Things that reduce inflammation do so by suppressing your immune system, so doctors tend to also prescribe antibiotics as a preventative measure, to minimize the chance of an opportunistic bacterial infection.

If you don't have any inflammation, then those drugs probably wouldn't do anything to help, and the immune system suppression might make it worse? On the other hand, it's not like you'll develop severe covid inflammation while taking what's essentially an inflammation sledgehammer. You probably did the best thing not taking them since your symptoms were mild and high dose corticosteroids are bad to take for no good reason, but it seems like what your doctor prescribed was reasonable if he thought your symptoms were bad enough.