Not sure how helpful this will be but I added that blocklist to my pihole and it is NOT blocking askubuntu.com. When I added it it parsed the following amount of domains.
Target: https://threatfox.abuse.ch/downloads/hostfile
[✓] Status: Retrieval successful
[✓] Parsed 6894 exact domains and 0 ABP-style domains (ignored 0 non-domain entries)
Target: https://threatfox.abuse.ch/downloads/hostfile
[✓] Status: Retrieval successful
[✓] Parsed 6894 exact domains and 0 ABP-style domains (ignored 0 non-domain entries)