Last night I was watching the chain for a while and saw a swap with two transactions in between, a classic sandwich.

Many people’s first reaction is "there's arbitrage opportunity," but honestly, the small price difference you see might just be someone paying you as a fee...
I also once got curious and tried to chase after a trade I didn't understand, and when slippage kicked in, the trade went through, but after calculating the net value, I realized I lost a chunk, and only then did I realize I was working for MEV.
Now my principle is pretty simple: if I don't understand it, I don't move, especially with projects that can layer on more yields (recently, the staking/sharing security approach being called "nested dolls" is normal),
if the yield curve isn't smooth or the risk premium can't be clearly explained, I’d rather miss out.
Anyway, as long as the money is there, it's fine.