For the transaction to actually take place it means that it needs to be appended to the blockchain, and whether it is appended or not is not up to you. Instead you have to rely entirely on others for that to occur. This is the very definition of trust.
there is nothing preventing you from running your own node or miner.
also, you are overextending the meaning of trust. Do you trust air when you’re breathing? Do you trust traffic lights? Do you trust you’re going to eliminate excess water through pee?
The point is that if you have a series of established rules and a way to verify that they are actually applied as designed, it does not really matter who applies them.
One miner cannot become a bad actor and invent its own rules.
The more correct answer is that your transaction has fees, which is why other miners are motivated to include it in their next block. (And also why a majority of the hashrate being centralized into a single entity with a singular will is a doomsday scenario for bitcoin.)
Of course, the concern that some particular miner might just have it out for you to a degree that outweighs this incentive, or who has some other incentive to not include your transaction, is more mitigated when there are more separate/independent miners/pools .
why would the miners discard a transaction and not another one given that the value they extract is the same?