Is there a reason why anti-wraparound autovacuum took around 42000 seconds to complete?

I have default auto-vacuum settings as follows - Autovacuum is running on a table with high-volume of insert operations. I have also applied a table-specific setting of autovacuum_freeze_max_age to 100000. Is there any setting I need to tweak to fix this? 42000 seconds sounds ridiculous. Please note that I am using postgreSQL 12.