You definitely don't need a 4.0 from Harvard to work at budge-bracket firms. In fact, at least one of the firms you listed hired literally no-one from Harvard in their latest analyst class! I would say that all undergraduates looking to get into finance should apply to all the bulge-brackets, not none of them.

Depends on what you mean by "apply." If it's someone who just read this guide, has been studying finance for a few weeks and goes ahead to fill out the online app for the next internship program, there are much better ways for them to make use of their time, unless they're very well qualified on paper. These positions are insanely competitive and they mostly go to either people with extensive networks and contacts in the firm, or people from target schools.

If it's someone who has networked with people in the firm and has contacts/alumni who will push their resume forward, then they should apply, but at that point the person will have learned enough to surpass the bounds of this guide's advice.

Many of the big banks run affirmative action programs; it is easier to get hired if you are not a white male. Indeed, I know one bank's HR complained that there were no good black undergraduates for them to hire because their competitors had been offering them internships and scholarships since freshman year.

True, but some people believe there is difficulty in terms of long term acceptance and fit in the industry. And small firms don't have affirmative action programs.

You should probably mention that IB is full of jocks

How many investment bankers do you know?

every EA who tried it has dropped out because of poor culture fit.

How many? If the number of EAs who tried it was small, then this isn't good evidence. It's not even clear to me that "being an EA" is a sufficiently descriptive reference class.

Either way, I should definitely not mention that fact, because that will give people biases and preconceptions. When they are learning about a career for the first time, they should start out with good, neutral sources, not secondhand rumors about people dropping out.

You are double-counting: buyside research is the same as asset management. But when people say 'equity research', they typically mean sell-side.

I have seen people talk about both buyside and sellside ER.

Isn't one purpose of effective altruism to be "clever in understanding human needs"? If we aren't spending dollars in any more effective ways than regular folks are when they spend their paychecks, we have failed miserably. In the current climate, it is still quite possible to do a tremendous amount of good with relatively few dollars. There are probably several organizations that can either save or drastically improve a life for less than $5,000. I can't imagine that ordinary people are spending their money during the course of their day in a manner that even approaches this sort of highly leveraged effectiveness.

The purpose of charity in the first place is to do more good than we would normally do when spending our money. Otherwise, we would have no good reason to ever donate to any charities. The purpose of effective altruism is to identify the very best ways of spending money in order to do the most good. If we aren't even beating the average Joe's personal spending habits, why are we here?