I was just thinking in the back of my head about how cheap LEDs have made types of lighting that would've cost way too much (both to install, and in electricity usage) no longer stupidly expensive.
For example, I noticed on Amazon some cheap furniture that has LEDs/power outlets sort of integrated right into them. Looks pretty cyberpunk-ish to my eyes. And I know years ago that sort of thing would've been marked up to high heavens.
Fancy lighting in general has changed drastically in price/design.
So...what are some things, due to changes in demand or changes in tech or changes in anything...that would've been really expensive back in the day, but which no longer seem to be, making them more frugal than they used to be?
In the pre- cellphone era, you would pay for telephone calls by the minute, and you would be charged a different rate if you called someone who lived out of your area. Like, a different rate per minute to talk to them? (I'm an Elder Millenial, so I grew up hearing about this stuff but didn't live with it in my adult life, I just vaguely remember the adult freak-outs about unsanctioned long distance calls...always due to the impending huge telephone bill you'd get for it.) My point being, companies like AT&T (Ma Bell) had an utter stranglehold on telecommunications and would make you pay out the nose to call someone out of your area in the same country, and international calls were even steeper.
This was an age where the telephone company monopoly was so bad that they were forcibly broken up into smaller companies by the government to force competition and a better market for consumers. (Imagine if, say, Amazon, was forcibly broken up into smaller companies by the government.) https://en.wikipedia.org/wiki/Bell_System
In the digital age, I can basically call someone in the next room as cheaply as I can call someone in Australia. (Speaking from a USA pov.) One of the few things that's better in the 2020s is how easy/cheap it is to call people now. (And text, and email, etc.)
I grew up in that era. I'll add that, the area code of your telephone number was dictated by where you lived. You could only make "free" calls (included in your monthly bill) to the same area code. Different area codes were considered long distance and incurred a per-minute additional charge. I had friends and relatives that lived an hour away, but calling them was considered "long distance". Given the price of gas at the time, it could be cheaper to drive to them to have a long conversation.
Another "world" we no longer have is the age of "collect call" and "calling cards". Collect calls meant you were calling someone, but they accept paying the charges. This was often used if you had to call someone from a payphone and didn't have money. Or, you had to call your parents long distance from your friend's phone and didn't want to charge it to them.
Then there's the "calling card". These allowed you to pre-pay for calls. You used to be able to buy a card at gas stations, drug stores, etc. that had prepaid domestic and long distance minutes on it. You'd call the number on the card first, enter the card info, then enter the telephone number you were calling. When you ran out of minutes, it would just hang up. Sometimes a voice would come onto the line and warn you that your time was almost up.
House phones were a great source of entertainment in the 80s. If you dialed zero, you were connected with a live operator you could prank. There was no caller id, so just dialing random numbers to prank was fun. Always in the same area code though. Otherwise your parents would get a charge on the bill at the end of the month and you'd be toast.
I never experienced this myself, but your comment here reminded me that in rural areas, some people's homes would be on a "party line". Meaning, one phone number for several houses, and I guess all the phones in all the houses on the party line would ring if it was called? And neighbors could just pick up their handset quietly and listen into calls and snoop and get gossip that way if the people talking didn't watch what they said over the phone?
And even in homes that had their own dedicated number, you could quietly lift any phone handset in the house and listen in. If you were careful the other people talking would never know someone else was listening in.
I never experienced the "party line", but having my parents or brother try to eavesdrop my calls by picking up another handset was a constant problem. I remember me and friends pausing or conversation at the slightest click noise on the line in fear someone was listening.
Later, when we got our first home computer and modem, my new problem was people picking up a handset while I was connected via modem. It would kill my connection every time. I used to get so pissed.
These calling cards are also the format that SIM cards are based on. It could store contact names and phone numbers (and most SIM cards still support this, although it's largely deprecated for smart phones) so you'd have a contact list ready to go.