I'm not agreeing or disagreeing, but how did you "count" to arrive at the 79% figure?
EV chargers are quite expensive items to build; somewhat less if you happen to be Tesla and mass manufacture them. Then there is maintenance, billing, someone to listen to the complaints (and act on them), pay for electricity (when in use and even when not, for lighting and security), data/network charges, vandalism, rodents, weather, rough use, and a few consumable parts (springs, filters, etc). There is also the growth pain: early on, they were under-utilised, which is costly, now they are in high demand, so you have capital expenditure to expand the network, etc.
Finally, electronic parts are still somewhat difficult to procure (especially if you're a smaller player), following the pandemic market shift and chip fabrication plant fires.
I'm not saying that no companies are not ripping us off, or there aren't those that are severely under-performing on maintenance / reliability, just that I'm glad that someone else is doing all that work, and not me.