My 1981 240D somehow has the original paint on it. Did anyone ever figure out to keep the factory paint from clouding up on these cars?

I had the paint cut yesterday, it looks great and I want to keep it that way. My experience with these back in the day was that nothing would stop the oxidation back then.

Any new products that have proven to eliminate this? I mean specific to these old single stage factory paint jobs.

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1981 240D Four on the floor, Orient Red over Parchment, bought with 154,000 but it's a daily driver and up to 180,000 miles, mostly original paint and all original interior.