Because almost every node runs Core, those defaults function as Bitcoin’s rules in practice. A miner who receives such a transaction directly can still mine it, and the block stands. Core won’t relay these transactions so processing one requires going through a miner directly. Services like MARA’s Slipstream exist to handle large, complex transactions.
On the other hand, DOG Mode would raise the maximum standard transaction from 400,000 weight units to 3.9 million. A Bitcoin block holds four million weight units, so Core currently relays nothing larger than a tenth of a block, while DOG Mode would carry transactions filling nearly all of one.
It would also cut the dust limit, the floor below which an output is considered too small to bother relaying, from between 294 and 546 satoshis to a single satoshi.
Ordinals, which embed images and text directly into transactions, and Runes, which issue tradeable tokens on Bitcoin, both have to pad their outputs with extra bitcoin to clear that floor. Leonidas claims removing it would release about $25 million in padding back to those ecosystems.
BIP 110, the proposal to cap arbitrary data, is a user-activated soft fork needing 55% of miners to signal support. It has drawn zero in the current period and has never cleared roughly 1% in any period, according to the BIP 110 monitor. It rewrites the rulebook, so it needs the network’s permission and cannot get it.