A lot of these sytems are ones that aren’t being used by the US anymore, and are in storage.
To name a couple of examples:
The Sea Sparrow RIM-7 was replace din US service by the RIM-162 ESSM, starting around 2000. I don’t believe any USN ships still carry the RIM-7
The M113s, MRAPs, and HMMWV are all in the process of being replaced in service by other systems - the DOD is giving away MRAPs to police departments because they don’t want or need them.
The Bradleys being supplied are the A2 ODS (I believe) versions, and have been replaced in US Army service by the A4 version.
So, while we are technically “depleting” our military strength, I don’t see any major concerns. In fact, you could even argue that using up this weaponry on killing Russians is cheaper than de-milling them. Can you imagine the cost of meetig all EPA regulations to take apart a Sea Sparrow missile and getting rid of the propellant and explosives?