Should port forwarding for running bitcoin be done also on the ISP's router? Follow up question on What is the NAT traversal technique used by bitcoin.

The network architecture described here https://superuser.com/questions/1109859/2-routers-connected-in-series-and-port-forwarding is something that I (probably) have in my home (and probably 99% of other people):

Internet &gt; ISP router (NAT 1) &gt; My home router (NAT 2) &gt; My Node


So my Node is hidden behind 2 NATs. Therefore I should forward ports on both routers to allow incoming connections to my Node.

But people have no access to NAT 1 and can only port-forward NAT 2, and must probably contact ISP to port-forward NAT 1.

How do people run their nodes with incoming connections enabled when this issue is present?

EDIT: In discussion with lenlord it seems that his ISP's router does not perform NAT and that his home router has (dynamically) assigned public Internet address. Is this the standard configuration ISP's provide for homes.

EDIT2: After contacting the ISP and reading some forum posts I found out that I'm indeed behind their NAT (NAT 1 in picture, so called CG-NAT), but that they can remove it for me for free.
In discussion with @lenlord it seems that his ISP's router does not perform NAT so that his home router has (dynamically) assigned public IP address.

After reading some forum posts and contacting the ISP I found out that some ISPs (and mine is one of them) do indeed hide households behind their NAT (NAT 1 in picture, so called CG-NAT), but that they can remove this NAT for free on demand.

Remove this NAT on the ISP's router is needed to operate bitcoin node with incoming connections.