I don't know what you meant exactly by "the western world", but this advice seems to really only apply to a part of it. There are numerous legal traditions (cultures?) around the world, and not all of them require everyone to get legal advice/help.
As an example, any legal culture where precedent isn't as important as in the USA is much more accessible to laypeople — you can actually read the law, understand it, and be reasonably certain that you found all the applicable laws.
As another example, there are places where courts take mostly intent into account, instead of deciding based on how a comma was placed in an agreement. In these jurisdictions the best agreements are short, clear, understandable, to the point, and do not require a lawyer to draft them.
I avoid mentioning specific countries that I know, for two reasons:
a) knee-jerk downvoting based on opinion has recently become widespread on HN,
b) there is always someone who instead of discussing the general point will find a nit to pick with a particular part of one of the examples.
Its a fact that our lives are fully dominated by the laws and regulations of the countries that we live in. If you don't have the time, or wherewithal, to understand all of these legalities (and few of us do, unless we've done law school), then it really pays to have an expert available to do that for you. Its unfortunate, but true: so many times, not knowing what is legal and not legal will get you into trouble - especially if you are entrepreneurial, and want to seriously have an impact on the world around you.