\"For deeper reorgs of 10+ blocks, the attacker would need to mine on average 80 work objects faster than the honest chain. [..] the attacker would have a 50% chance of success after 5-6 years of selfish mining. With Nakamoto consensus, the attacker can expect to achieve several 10-block reorgs per day.\"

https://monero.observer/tevador-proposes-share-or-perish-selfish-mining-mitigation/