It seems to me (leftish) that it's pointing at something correct but oversimplifying.

In so far as Lycce's analysis is correct, I should be looking at people in difficulty and saying "there's nothing wrong with their abilities, but society has screwed them over, and for that reason they should be helped". I might say that sometimes -- e.g., when looking at a case of alleged sexual discrimination -- but in that case my disagreement with those who take the other position isn't philosophical, it's a matter of empirical fact. (Unless either side takes that position without regard to the evidence in any given case, which I don't think I do and wouldn't expect the more reasonable sort of rightist to do either.)

But it's not what I'd say about, say, someone who has had no job for a year and is surviving on government benefits. Because that would suggest that if in fact they had no job because they simply had no marketable skills, then I should be saying "OK, then let them starve". Which I wouldn't. I would say: no, we don't let them starve, because part of being civilized is not letting people starve even if for one reason or another they're not useful.

We might then have an argument -- my hypothetical rightist and I -- about whether a policy of letting some people starve results in more people working for fear of starvation, hence more prosperity, hence fewer people actually starving in the end. I hope I'd be persuadable by evidence and argument, but most likely I'd be looking for reasons to broaden the safety net and Hypothetical Rightist would be looking for reasons to narrow it. That may be because of differences in opinion about "personal responsibility" (as Lycce suggests) or in compassion (as I might suggest if feeling uncharitable) or in realism (as H.R. might suggest if feeling uncharitable) but I don't think it has much to do with societal influence trumping individual capabilities.

I think Lycce's analysis works better to explain left/right differences in attitudes to the conspicuously successful. H.R. might say: "look, this person has been smart and worked hard and done something people value, and deserves to be richly rewarded". I might be more inclined to say "yes indeed, but (1) here are some other people who are as smart and hardworking and doing valuable things but much poorer and (2) this person's success is also the result of others' contributions". And if you round that off to "societal influence versus individual capabilities" you're not so far off.

In uncharitable mood, my mental model of people on the right isn't quite "self-interested and evil" but "working for the interests of the successful". (When in slightly less uncharitable mood, I will defend that a little -- success is somewhat correlated with doing useful things, thinking clearly, not harming other people too overtly, etc., and there's something to be said for promoting the interests of those people.)

I would guess (not very confidently) that people on the right will be more inclined to agree with Lycce's analysis, and (one notch less confidently still) that Lycce identifies more with the right than with the left.