I have tried in the past and I am just not good at understanding all of it. I think there was 1 (Chase Sapphire?) I was seriously considering but it didn't seem to add up as well as you put it - not doubting you, but I just don't understand it completely. I feel like there needs to be a for-dummies YT video on this topic.
It's nothing more than signing up to (mainly) Chase credit cards and getting the bonus points, then getting a new Chase card, getting the bonus points, etc.
It's always "spend $X amount in Y months to get Z bonus points" and those terms can vary just depending on the card.
The Southwest cards are what I get as often as possible because of their companion pass. Basically, if you get 125k points in one calendar year, then for the rest of that calendar year and the following year, someone can fly with you for free. And you can get 125k points in bonus points from opening 2 of their cards. So after that, you can book your own flight with points, and then get someone to fly for free with you. The only catch is you pay taxes on the flights, which can vary from $5.50 one way domestic, to $90 one way international.
So typically I will open a SW card around like January if I can, then get the bonus, then open another SW card after, and I'll have the points + companion pass for the rest of the year and the following.
The catch is you can only get these bonuses every 24 months, and can only get 5 Chase cards in 24 months as far as bonuses go. But for the SW cards, my wife and I basically take turns opening cards each year, so by the time it's my turn to open another SW card, it's nearly been 24 months.
I just booked 4 flights to Aruba this morning. I paid $360 total in taxes. I booked mine with points and my one son is my companion for the rest of this year, and then I booked my wifes with her points and our other son is her companion. Earlier this year we also went to the Keys and I paid $44 total doing the same thing. And we're going to Belize in November and it's going to be $400 in taxes. In July just my wife and I flew first class to Colombia for free with Chase Ultimate Rewards points.
The CUR points are good too because you can transfer them to some airlines and they transfer 1:1. United has great "saver" flights and sometimes "super saver" where they have really cheap flights with points. We had 150k bonus points in my wifes account and the first class round trip flights were 74k each, so we opted to use all her points for that. We transfered from Chase to United and got those flights. We've also flown to St. Thomas for like 21k points round trip per flight with one of those Super Saver deals.
All that said, you can see how much money it saves. We're now a family of 4 and flying to all those places would not be remotely possible without points. Just this year alone I mean I'm probably saving like over $10k. And I've been doing this since like 2010 when I first found out about SW points. Thankfully we live about 40 mins from 3 international airports and one is a SW hub and one is a United hub. I think the other is an American hub but we rarely fly out of there.
EDIT:
Literally yesterday I was booking our flights to Belize and ran into an issue. I booked mine and then my wifes, and I went to add my son as a companion but got an error. Then I tried adding my other on her account and it errored as well. SO I called them and it turns out we literally booked the last 2 seats on the 2nd leg, Houston to Belize, and there were no more available seats.
So I had to cancel the flights and we had to "settle" on going to Aruba instead. We wanted to take our kids to Belize since they haven't been there and they've been to Aruba, and we've been there a bunch already and Belize just once. But yeah, kind of a good "problem" to have I guess lol.
So just one thing to keep in mind if you are using companion pass. Make sure when you search, you search for your total passengers first just to make sure there are enough empty seats on the plane. I assumed there was because I saw the other 2 types of flights available when I booked it and that it meant there were more seats available. But nope.