Recently, a bunch of memes and celebrities shouting orders have been pulling attention back and forth.

Watching the active addresses on the chain surge and retreat, it’s quite like a relay race where everyone tries to grab the last baton.
Speaking of block builders and bundles, retail investors don’t need to turn themselves into researchers; just knowing that they can be "cut in line/blocked" is enough:
Your transaction isn’t directly reaching miners/validators; it might be bundled into a chunk, and then someone might insert stuff before or after you to profit from the spread.

I used to worry about how each role divides tasks and how MEV runs… now I focus on more practical things:
If you’re really buying or selling, don’t chase the green candle at the exact moment; don’t go all-in when liquidity is thin.
Use reliable wallets/routes, don’t set slippage too far off.
For large amounts, split the orders and be patient.
Anyway, what you need to guard against isn’t “technical terms,” but your own urge to become liquidity.