Without a doubt, trading is more stressful than investing, but that doesn't mean that investing in Bitcoin is stress free, because it still has it own psychological stress attached to it, especially when your mind and thinking are always there, but in trading you are stressed emotionally, psychological and physically, that's why it's way more difficult than investing in Bitcoin.
It all depends on the investor’s entry point. I think that early BTC investors aren’t experiencing much stress, neither now nor in past cycles, because no matter how severe the current correction is, they’re still sitting on huge profits. At the same time, if a beginner investor bought BTC near the ATH and got in at a bad time, they will certainly feel stress during a bear market, just like traders constantly do, especially those who trade frequently.
They are in huge profit now which indeed cuts the stress but what about in the past, when things are still or also uncertain? But that is if they are only in for business/profits, and they only treat their BTC for investment, nothing more. Because in the past, I'm aware that there were also people that joined BTC only because they like its technology. I won't say though that these people have less expectations. It is clear that it is not only the money that matters in this world but once the underlying technology is a success, money can also/just come naturally.
Still, it may not be as much as the other type. What do you mean there BTW mate on your last sentence? That traders feel stressful too? But yeah, I mean stress is already part of a human being, unless you are not normal or you are an AI

. However, traders are still more versatile. They can always adjust and still make profits even though they accidentally buy at a pump, most especially those that trade frequently, as that may mean that they are more experience or well-skilled already.