Well, my bike cost me about $500 initial cost with some accessories 2 yrs ago. I spend about $100 per year on maintenance and repairs so far. So total cost so far is about $350/yr. I expect the bike to last quite a few yrs. So the average annual cost will go down. significantly.

My beater pickup cost me $2800 7 yrs ago with trade-in. I have spent at least $500 per yr on maint and repairs. Part of the reason the average price is that low is I have been bike commuting the last 4 yrs. So that comes to about $900/yr with assistance by the bike.

I am also looking for a replacement pickup. So add another initial cost onto the ledger. I will be lucky if initial cost minus selling the beater is less than $4000.

So yes. For me the bike saves me money. As tsl says you don't have to spend lots of money on yours. You have the choice. Nothing wrong with upgrading tho.