One of the things that I've noticed during my time on the sidelines watching straight people date is that the guys I'm friends with who are very successful with women are pleasant to be around and often genuinely kind. That's not to say that all of them are necessarily the best partners in the long term and just like anyone else they may still cheat or drink too much or do any number of the many things that might blow up in a relationship, but generally their gut reaction to a situation where someone else is in trouble is to help, even if it puts them out or puts them in danger. It's easy for RPers to hamster away women liking this in violent situations like sticking up for someone weaker in a fight, but I've seen women respond very positively to things like my friends giving a homeless man their jacket, going out of their way to look out for a drunk stranger and pay for their ride home or verbally defend a less attractive friend (or even stranger).

The most obvious response to this is 'well this is beta, it's not increasing SMV, just RMV', but I would argue that selfless displays like this actively increase actual attraction. A man who gives a homeless man his jacket isn't a penny pincher or someone who doesn't know if he can afford a new one, a man who takes time on a night out to look after a drunk stranger instead of chasing tail clearly isn't desperate, and a man who defends someone else from insult isn't afraid of the competition than might come from boosting someone else up, and what all of these men have in common is that they have the confidence and capacity to do what they think is right in the moment.

Where people get confused is in conflating kindness alone with the truly toxic combination of kindness and passivity. Being kind and passive is often worse than only being passive because it creates situations where you can empathise with other people but lack the confidence to help them or the assertiveness to stand up for yourself when people try to take advantage of you. A woman can then see you want to intervene but hold yourself back or confine yourself to complaining, which makes you look weak, or you'll let people walk all over you because you're empathetic enough to see their point of view but have low enough self worth that you feel guilt about asserting your own interests over theirs.

RPers correctly identify the issues with passivity and address that, but often ignore or actively excise the kindness that can come with it. In men that aren't naturally inclined to be kind this isn't necessarily a problem as there are other ways to signal abundance and confidence, but in men who do want to be kind this creates bitterness and frustration that can push them towards being aggressive and cruel because they feel they need to overcompensate to overcome the gentler parts of their nature. For men like this training themselves out of the neuroticism and self doubt that prevents them from acting on their nobler impulses in public and actively seeking out activities and situations where they can display magnanimity from a position of power can allow them to attract women without compromising on their beliefs. This can be harder than other methods of signalling because it's more difficult to find opportunities to display it and you can end up walking a fine line between being giving and being needlessly self-sacrificing, but I'd argue that for kind men it can often be better to pursue the harder route and maintain inner harmony than constantly battle to change something about yourself that really doesn't need to be changed.

tl;dr: people misattribute the repulsion that the combination of kindness and passivity creates to kindness alone, and it's possible and even preferable for some men to attract women with displays of kindness and magnanimity provided it's balanced with confidence