Ugh, right? I was the same way for years. I wrote off light roasts as just sour and weak. Then I tried a properly brewed Ethiopian. Those blueberry notes hooked me instantly. Now my dark roast French press just tastes like burnt toast. I do miss that heavy comfort sometimes.
My brother has been on this light roast kick for months now. He talks about blueberry notes just like rubyb21, but I don't get the hype. It's coffee, not a religion, so why make such a big deal out of it. Your taste buds might like something new, but that doesn't mean you betrayed anything. Drink what you want and move on with your day.