Many of those things can be as cheap or as expensive as you want, the last two do have some cost of entry but, it entirely depends how deep you want to go.
I enjoyed gaming as a kid, but the older I become, the less tolerant of it I am. I was the sort of kid/teen that would dive deep into JRPG's and spend time on gamefaqs.com and other forums - so don't discount me as someone that never understood gaming - but now that I'm an adult I just don't enjoy it. Maybe it's because I understand how games are made, and what meetings/background context goes into publishing a game, maybe it's just that I have less and less freetime so I don't want to be involved in a computer-esque realted software type deal. There's also the whome gamification of society and microtransactions that really draw developers into extracting money every chance, and theres also marketplaces like Xbox Game Pass that offer unlimited gaming for a set fee.
I very much think we are in a true golden age of information exchange - letters - phone calls - instant transmisison via Internet to the point where we're conversing ways to relax with the time we have. And I don't mean to be negative of your hobby. As long as you enjoy the time you spend on it - that's excellent. :) And don't think I don't game now, I have a switch that I never use with a library of games that keeps piling up - heh.
I also enjoyed gaming more as a kid. I found it easier to suspend my disbelief when I was young, and my patience for grinding/clunky interfaces was higher. I've never played a game with microtransactions, seems dangerous!
People pay $20 to be engrossed in a movie for 1.5 hours. Is that addiction?
https://store.steampowered.com/app/646570/Slay_the_Spire/
https://www.gog.com/game/sid_meiers_alpha_centauri
https://store.steampowered.com/app/219740/Dont_Starve/ (would recommend going into this game as blind as possible)
https://store.steampowered.com/app/368230/Kingdom_Classic/
https://store.steampowered.com/app/107100/Bastion/
https://store.steampowered.com/app/662540/Haque/
If you like puzzles, my roommate (also an engineer) was a huge fan of https://store.steampowered.com/app/736260/Baba_Is_You/
Usually I try to monitor prices using a site like isthereanydeal.com and wait until it's discounted at least 50%.
A mistake I made in the past was buying games just because there was a really good sale. At a certain point, I realized that the time investment in learning new game mechanics is more important than the cash investment in buying the game. Investing your time in learning the mechanics of a mediocre-but-cheap game isn't a great way to relax.
Another strategy is to use a site like ifttt.com to get alerts for free games on the /r/GameDeals subreddit. You can accumulate a large game library for no cost at all if you're patient enough.
I always like to play on an HDMI TV with a gamepad if possible; hunching over a laptop isn't very relaxing. Almost all the games I recommended above have good gamepad support. Steam has a nifty Big Picture mode that makes it easy to browse your library with a gamepad.
Beware: Having a game library that's too large may cause decision fatigue which makes gaming less fun! :-P
I'm weirdly happy for you that this is your failure mode. For most people, buying games on sale just leads to a bigger and bigger backlog of unplayed games.
The backlog thing is part of why I think we're in a golden age. I remember when I was a kid, it was common for my friends to own a game console (Gamecube, Gameboy, etc.) with less than 5 games for it. We're in an age of abundance now compared to those days.
I try to view my backlog as an asset, not a liability. Think of it as a garden of unexplored delights. It's just a matter of giving a new game 5-10 hours to prove itself to you as you master its mechanics, instead of skipping on to the next game if you aren't immediately hooked.