Lately, I've been seeing everyone talk about blockchain builders, bundles, and so on, and it feels like retail investors really don't need to push themselves to become "semi-researchers."

All you need to know is: the transactions you send out don't necessarily get included in blocks in the order you want; others can bundle several transactions together and insert them, while also sneaking in some stuff before or after to profit from the spread (in simple terms, you become liquidity).
So the key isn't to memorize a bunch of terminology, but rather, when dealing with slippage sensitivity, hot pool trading, thin liquidity cross-chain operations, don't just click default settings blindly;
use private/protected modes when possible, don't combine token swaps, bridging, and opening positions in one transaction—breaking them into smaller steps might actually help you avoid pitfalls.
The recent testnet points system is the same—everyone's eager to see if the mainnet will issue tokens, and the more impatient you are, the more likely you are to hit strange routes and bridges, ending up stuck in a dilemma.
Anyway, I personally prefer to wait for an extra block.
That's all.