domain name system - Why do Network Solutions DNS servers answer an incorrect IP for google.com etc.?

Network Solutions DNS servers (ns1 - ns99.worldnic.com) answer the IP 141.8.225.31 for any A query to which they do not hold the answer. E.g.:

C:\>dig @ns11.worldnic.com www.google.com
www.google.com.         3600    IN      A       141.8.225.31

For the corresponding NS query, they claim to give an authoritative answer that their server holds the SOA for that TLD.

C:\>dig @ns11.worldnic.com www.google.com NS
;; flags: qr aa rd; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1
;; AUTHORITY SECTION:
com.                    3600    IN      SOA     ns11.worldnic.com. dns.worldnic.com. 2016010801 3600 600 1209600 3600

The same results occur for any name for which they are not authoritative, e.g. previous customers like metacase.com, or non-existent names like xyxyxyxyxy.net. All return the same IP, which is for a spammy advertising site in Switzerland.

This seems incorrect. Although normally ISP DNS servers will not query Network Solutions for these names, when a domain is transferred away from their name servers many ISP DNS servers ("child sticky") continue to ask the previous name server as long as it claims to answer. Thus a domain transfer (or change of authoritative name server) results in a loss of connectivity for that host, even if the host's actual IP remains unchanged and was correct in both losing and gaining authoritative name server.

Full dig output for the above queries:

C:\>dig @ns11.worldnic.com www.google.com

; <<>> DiG 9.11.3 <<>> @ns11.worldnic.com www.google.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 44870

;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 2800
;; QUESTION SECTION:
;www.google.com.                        IN      A

;; ANSWER SECTION:
www.google.com.         3600    IN      A       141.8.225.31


;; Query time: 154 msec
;; SERVER: 207.204.40.106#53(207.204.40.106)
;; WHEN: Mon Apr 09 13:22:19 FLE Summer Time 2018
;; MSG SIZE  rcvd: 59


C:\>dig @ns11.worldnic.com www.google.com NS

; <<>> DiG 9.11.3 <<>> @ns11.worldnic.com www.google.com NS

; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 50950
;; flags: qr aa rd; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 2800
;; QUESTION SECTION:

;www.google.com.                        IN      NS

;; AUTHORITY SECTION:
com.                    3600    IN      SOA     ns11.worldnic.com. dns.worldnic.com. 2016010801 3600 600 1209600 3600

;; Query time: 151 msec
;; SERVER: 207.204.40.106#53(207.204.40.106)
;; WHEN: Mon Apr 09 13:22:32 FLE Summer Time 2018
;; MSG SIZE  rcvd: 97