Is being a Heretic Titan lame because you're no longer an Exalt? Absolutely not, because you're still an Exalt. Sure, we have an example that Infernals and Solars can become Primordials, but that's a step backward so they don't do it if they know any better (keeping in mind that player characters don't have perfect information; canon-wise GSPs know they can become Yozi. They don't even know that Heretical charms exist, much less the Triumphant Howl of the Devil Tiger tree).
But, we have an example of the opposite. When you go the Devil-Tiger route, its not the Exalt part that you get rid of, it's the
human (every human trait possible except for your soul such that you're functionally a different kind of being but technically still human) part. You become Titan
(with a human soul so you're technically still human even though you're functionally different in every way) + Exalt. Solars, Sidereals, Lunars, and Terrestrials could all have a similar option, where they become Something
(that is still technically human but functionally different in every other way) + Exalt.
I see this complaint a lot, but I think its a clear example of a fallacy of false dichotomy. Yes, there is nothing better than being an Exalt, but there is something better than being
human (having all human traits except for a soul, which you'll keep so you're technically still human even though you're functionally different in every way that matters).