Currently I only have one, as I don’t need more, but I can easily get one per computer.
Just like I can get one phone number per room.
Very few ISPs let you do that and if they do, continuous blocks are really expensive these days, even for servers. For end user networks it's even less likely that you get them. Maybe in the states, but not in Europe. In Germany especially there are many ISPs that do not give you any IP address any more but have a carrier side NAT unless you call phone support or switch it in a panel somewhere and then you get exactly one dynamic IP that rotates every 24 hours.
If you have an ISP that gives you anything larger than /24 I would really like to hear which one that is.
Those, like TNG, often offer far better contracts.
First of all we're reaching the point where we basically discuss a tiny part of the overall space and as such this is not even relevant to the original point any more.
Secondly, the ISP you named (TNG) does not appear to even give out blocks for customers.
The "small ISPs give out multiple IPs on request" is a different, but related part.
It’s effectively like the standard 24h dynamic IPs, just that they never change them. You don’t own the IP, but are still guaranteed to be reachable under it.
You have one IP, not one per computer. Thus your router becomes a NAT for the devices you have internally.