insecureSkipVerify on internal network

I was trying to get rid of "Your connection is not private" prompt every time I try to access local services over HTTPS, so I integrated Traefik as reverse proxy.

Since my services can't be accessed over the internet I used DNS Challenge to get a proper certificate. Then for containers I want to use TLS I added these two labels in docker-compose.yml:
traefik.http.routers.<service-name>.tls.certresolver=myresolver
traefik.http.routers.<service-name>.tls=true

Then I tried to enable insecureSkipVerify and noticed that I don't even need proper certificate. It seems to be enough to just add traefik.http.routers.<service-name>.tls=true label and the connection becomes secure. So no need for certresolver parameter.

Do I understand it correct that in order to have TLS working on local network, I don't really need a proper certificate and that it is enough to just set insecureSkipVerify to true?