You are absolutely right. Was a stressful morning sorting this out, thanks for the response.

Yes definitely just ran into this myself. I think i had the opposite problem of OP. I have only ipsec VTI on the router, but whenever a reset vpn ipsec-peer command was run, the peer IP was being added as default route for table 220. Furthermore, this was being respected as the default route for the system (I'm not sure how route priority works with tables, but i'm guessing table 220 has preference over table main?)