It is absolutely so much cheaper.
Mostly from space and amenities to comfortably cook for yourself, grow your own <deleted>, build your own <deleted>, maintain and repair your own <deleted> (vehicles etc). That being said, if you're not willing to put down for a house and some land and not willing to be proactive with almost everything, then it's not for you.
When you're ready for that managing personal finances and cutting costs will be much easier, also less temptations around here. I cook 90% of my own foods, do all my bike repair and maintenance myself, grow a bunch of fruit, herbs, veggies on site. Whatever we don't have at home is extremely cheap in local fresh markets and they are actually fresh. I live around 7k from Udon Thani city, and even in town restaurants, coffee shops, gyms, bars are half price from larger cities.
I make roughly 100k a month and living in Bangkok I had 10k to save monthly, in Pattaya maybe 20k and in Udon Thani I don't spend much more than 50k on everything.
Some words to end this with, while many basic necessities are somewhat cheaper, moving to "the sticks" makes you change your perspective and lifestyle to be less reliant on outside services = lower cost of living, increased value.