Militarization of the police was a pretty big change.

It's less noticeable in most rural areas, but some places the police have unexpected access to hardware. Think of towns of ~1000 people that have anti-riot vehicles. That kind of access came after increased security spending after 9/11. A lot of police departments saw it as money from the heavens and were worried that if they didn't spend it, they wouldn't get more of it.

There has also been an increase in police officers carrying gear that used to be restricted to SWAT teams. I've worked in a couple major cities where every day I had to walk past cops that were basically just standing around with an M4A1 strapped across their chest and their hand resting on the grip.

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The mortgage crisis around 2008 completely changed the way that homes are bought and sold. If you bought a home before that time you had to do way less paperwork and way less work to prove that you can afford the McMansion you just bought.

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The dot-com crash in the 90's fundamentally changed how startups are funded and valued. Before that crash startups didn't need to have any plan to profitability. VC decks were basically:

    1. Steal underpants

    2. ???

    3. Go public

    4. Profit

VCs still invest in bubbles, but you need a much clearer picture of how you'll become profitable one day. Amazon is a notable hold-over from those days. They've never technically turned a profit, and have no real plans to.