There is no advantage of slow charging at all. My estimate is that a slow, public charging point costs 5k to 10k euro in a 10 year time span. That money comes from your pocket and you get nothing in return.
We've been over this before.
Let's pretend your 10k euro cost is correct. I would argue it is not, but for the sake of analysis let's go with it. If the electricity is just 0.05 EUR extra per kWh above the cost price (ex VAT, other taxes etc.), then 10k euro takes 200,000kWh to pay back. That is 28,500 hours of charging at 7kW. There are 87,600 hours in 10 years, so that charger only needs to have >1/3rd occupancy to be profitable.
Now the reality is that installing ten chargers in one street/car park costs much less, per charger, than one charger, because the infrastructure is shared. It may cost just 1,000 euros per space.
Car parking spaces themselves cost some 20,000 euros each to construct. Many of them exist already, sure, but that is land which is dedicated to the car over being a shop or a house or something else. So it is not as if that land is free. EV charging offers yet another way to make money from that land.
Economically it's a no brainer.
You are also way to optimistic about how people deal with shared infrastructure. My asshole neighbour across the street will happily punch you in the face if you dare park in 'his' parking spot in the front of his home. The police had to come several times already to calm him down.
OK, assholes are assholes. Not sure what this has to do with EVs. The infrastructure will be shared just as street parking is shared.
Another problem is that (at least in the Netherlands) a parking space with a charger is no longer a parking space but a space where you charge your car. Once charging is done, you need to move your car (the fine is 90 euro). That just doesn't work with overnight charging; you'd have to get out of bed during the night to move your car (or be awakened by an angry neighbour that needs to charge a car).
The spots I've seen in London tolerate overnight charging from 8pm to 9am, even if the charging finishes before then. If you have enough infrastructure, it's not a problem!
One solution would be to have charging points with multiple outlets (say 6 to 8 ) that can serve several cars that are parked in a row without needing specific charging space, but that idea seemed not to have occured yet at the companies that develop / install charging points. And it would mean needing long cables that litter the street; it could be that regulations are blocking this idea already.
A four-way head is probably just about possible if positioned correctly but you may need a 8-10m long cable. Most cars come with 4m or less cable length, though you can of course buy longer cables. An issue with current EVs is that charge points tend to be on random spots all over the vehicle. Mine is under the VW badge up front, but the e-Golf is in the normal petrol filler place (as bodywork is ~same as petrol Golf). There needs to be consistency here. I personally prefer the charging position of ID.3/Ioniq 5/Tesla, which is rear on driver or passenger side. Ideally there would be a decision on just one side as well, but given manufacturers of petrol cars can't make their minds up on this I may be an optimist.
But that still doesn't solve the principle problem that public charging is very expensive to begin with. None of the companies currently active in the Netherlands is making money from their charging points. They will have to earn their money back at some point [...]
As you can see here and elsewhere I've justified how charging can be profitable even with small margins. The problem is that there aren't enough EVs. We need government subsidies or private investors to take a risk but it is very chicken and egg. Fortunately it seems to be turning the right way. I do think it will take the better part of a decade to have the right level of infrastructure though.