Other computers/customers of my Internet Service Provider appears under my “Network” section in Windows Explorer

other computers of my ISP appears here

viewing the network page

I could see many computers under “Network” section on the left sidebar of Windows Explorer, but I am the only one who uses computer on my home.

So I suppose all those computers are also using the same Internet Service Provider as me, and we’re both inside the same “local” network or so.

The network setup on my home is simple, just my computer connected to a Wifi Router, then to a fibre optic router/modem.

I don’t know if this is a security issue, but my feeling is that this is not a normal thing to happen.
So, is this a serious issue?