Thing is, having a secure and stable place to live (which doesn’t necessarily mean getting on the housing ladder) is a basic need.
And meeting that particular basic need is much, much harder for millennials, particularly in the South East (where there is the largest concentration of well-paid jobs, which is a different issue). I’m not a millennial, so have no personal axe to grind, but...
There are virtually no council houses in many areas.
There is virtually no security of tenure in private rented accommodation. And the ability to get higher LTV mortgages distorted the property market and concentrated property wealth disproportionately in the older generations, as they were the ones who had the money to put down multiple deposits.
Both rent and property prices have increased - yet salaries haven’t. As an example, I rented a 1-bed flat in the early 2000s for £550/month. I was earning £19,000 a year. Today, the same flat rents for £825/month, and bills have also increased. The equivalent job now pays £18,000 a year.
Yes, in many ways the standard of living generally is much higher now than in the past. Still doesn’t take away from the difficulty in getting this basic need met.