How is locally producing military equipment versus buying extremely expensive US uberl33t overkill hardware suppose to hurt the EU? It not like the US was just giving Europe free armaments.

Yeah sure they won't be producing any F35s or million dollar per shot missiles, but was that a good idea to start with? Are they worth the money when once again lots of inexpensive arms are shown to be more useful in modern wars than a few handfuls of expensive ones? Both Iran and Ukraine have shown that one side being a few steps ahead in military technology and willing to dump money on equipment still has limited returns. There is no "I win" technology apart from indiscriminately killing most of the entire population, which just makes you an existential enemy to the rest of the planet and erases 95% of the value in taking that territory.

Its really not that obvious to you? Because not having US bases on site and technology sharing and agreements takes money away from entitlements. France tried to cut entitlements by a tiny bit and the yellow vest movement was born. In the long run the Yellow Vests might end up losing everything as a result.

Regardless of the tech stack the work still needs to be done and now the EU has to do it. The Eu does not have infinite money, in fact they have less than the US so there will be cuts elsewhere.