What's the deal with on-chain queue jumping?

Honestly, it's mostly about who is being exploited—whose sheep are being sheared?
Put simply, most of the time it breaks the "expected transaction" for ordinary users: you click swap expecting to execute at the price you see, but then you're sandwiched, slippage explodes, and your transaction fails or retries... For someone like me who gets annoyed at signature failures, it's even more frustrating.

MEV isn't some mystical concept; it's just the monetization of ordering rights and information asymmetry.
The ones most affected aren't those who run their own nodes, tune RPCs, or monitor the mempool, but the default users: those who don't understand gas, don't watch slippage, and just want one-click confirmation.
As for "fairness," at the very least, you should know your position in the queue and whether you'll be inserted.

Recently, modularization and data availability layers have been hot topics, developers are excited, but users are left confused...
But ultimately, someone has to take responsibility for the transaction experience: no matter how beautiful the chain's architecture, if the ordering isn't transparent, it still feels like waiting in line to buy tickets and getting cut by scalpers.
Anyway, I now try to use private routes when I can, to avoid running naked in public pools.