We replaced our 2022 detector last fall for the same problem: hypersensitive, going off for no apparent reason. I also used Wago connectors to make the next replacement easier. I think the RV environment is especially hard on these detectors, especially in small campers like ours, where they're often exposed to low levels of various chemicals: propane from the stove, exhaust from the fridge coming in the screen door, even hair spray. Not to mention temperature extremes while in storage.
On another note, always disconnect power before cutting or splicing wires. It's easier to find and pull the fuse than to repair whatever damage you might cause with a short.