Something I realised recently when moving up in stakes was that I was more agitated when losing pots not because of the money but because I didn't know for sure that I was going to get it back in the long term because I didn't have a sample at those stakes. If I made a mistake it made me question if I was beating the game or if I was just punting the money I earned at lower stakes. As I played more and acclimatised and started to understand that these players were not unbeatable and had leaks that I could/would take advantage of to make money in the long term the odd slight mistake began to bother me less and I more had the mentality of just correct it and don't make it again.

Also just with respect to live vs online I think when you play live there's a complete certainty that you are crushing these people because they obviously treat poker very casually and make very obvious errors but online sometimes there's this uncertainty where someone does something weird that ends up working a few times and wins a few pots and you're not sure if they're owning you or just a fish on a heater because you can't see the hoodie and dark glasses or alternatively the pint of beer that they've brought with them to the table.

Im having kind of similar experiences tbh. My theorie is (speaking for myself) that its the much higher pace of onlinegames that highers the risk of getting tilted (in many different ways). If you get coolered live, you just take some steps, have a short joke with your neighbour or get an (sometimes) honest "nh" from your opponent and move on.
After getting coolered while playing 4 tables+ online is just another thing, because the action just moves on quickly.
I just realised this after playing zoom for about 2-3 years mainly and getting back to regular tables some weeks ago, that i feel way more comfotabel there (due to the slower game-pace). I guess even good players tend to get kind of robotic (which defo is a kind of tilt itself) while playing online, which basically never happens when playing live.

just tilt in live games as much as you do online problem solved works for me

Playing more hands?
For me it's the opposite, when playing live there are several things that can tilt me that don't happen online: Time per hand, lighting of the room, fullring tables, unconfortable chairs, people's smells!
But I rarely play live, only in some tournament events play some cashgames and the mains.

such a perfect post for me ironically at the perfect time. i have been dealing with this exact thing the the past 2 days as i just recently moved up and lost 12bis after crushing the lower stake the past 3 weeks, which took a huge hit to my br. i was super tilted and i thought to myself why when i lose 5-10x the pot live, im able to control my emotions better, same goes with when i play my normal stakes, i dont really care about losing a ton of bis. i think a lot of it has to do with questioning your ability to win, even if you have studied the pool and have good exploits, losing is something that our brains take really poorly which results in us studying a shit load more to avoid that pain. also considering the sheer amount of volume we get in online, 10 hours live you can do in about an hour 1 tabling zoom. so its really hard to lose 5bis in a day live, compared to playing 4k hands in a day, you can easily see -10bis or +20-30 which would be the equivalent of playing a full month live. i also think live we are more calm since its also social, and are more likely to tilt if we dont like people at the table, and online we remove any human association to an avatar so we can build hatred easily. like dnegs said, since you dont have a good sample size, you are unsure if you are winning which i believe creates dissonance for our brain since we believe we are winning, but also not sure. as for controlling your tilt, i would recommend meditation, listen to the elliot roe mp3s and really calm yourself down before and after sessions. it will help you with changing your outlook on situations, whether its strategy or things that are more important. for example, if you were offered infinite wealth for the cost of a loved ones life, you would obviously say no. of course thats quite dramatic but some things in life we need to give more emotional value to vs a card game. for me, my tilt has resulted in treating friends and family poorly. which meditation has helped and i treat close ones with more kindness nowadays.

Excellent responses from everyone. Social aspect, fast pace, letting your brain refocus, uncertainty at the stakes, etc. Everyone kind of hit the nail on the head. Glad we can share a common issue and analyze it and most importantly move forward.