Because a number of believers in the Trinity are ALSO believers in Hell it doesn't follow that these doctrines are logically connected. They aren't imo. If they are, as you have asserted countless times, please explain why and/or how.
The doctrine of Hell emerged in monotheistic second-temple Judaism rather independently from angelologic developments which provided the background for the heavenly "Son of God" figure; it was shared by pre- and anti-Trinitarian Christians, both of the Jewish-Christian and later Arian kinds; it was adopted by Islamic monotheism which opposed the Trinity concept right from the start.
Otoh the Trinity concept in more or less developed forms was perfectly compatible with views of universal salvation opposing the concept of everlasting torment like the doctrine of apokatastasis in Origen and Gregory of Nyssa; it is still the case with all kinds of universalist theologians; a number of modern doctrines also combine Trinitarianism with "annihilationist" views, like Seventh-Day Adventism or even a few Evangelicals like John Stott.
And please don't evade this question of the relationship between two DOCTRINES by moving to a "theory vs. practice" argument. If such a dilemma is valid it applies to ALL doctrines, not just the ones you happen to dislike...