When inviting users on this forum, they immediately get extra trust. Why is this feature a thing (not saying it’s bad)? For example, @Eltralor got trust level 1 when I invited this user. If you are invited by a higher TL user, then you will get TL2 like @steve_c .
Are you sure it depends on the trust level of the person inviting? Maybe he got promoted to tl 2 manually or was added to a group that grants a trust level. I think the level granted because of an invite is always the same.