A large part of the issue of Boomer-tier advice of "eat out less often and spend less on frivolous things" is not that it is bad advice. Spending less money on eating out and finding ways to save money can go a long way for your bottom line.
The problem is that Millennials and Zoomers can follow this advice to a T and still find themselves unable to afford a home where they live. The expensive home prices is the real issue, and it is a slap in the face to younger generations to ignore this fact