Thankfulness, gratitude, are inherently dangerous. Quite deadly, I think. Why? Because they are life based on external circumstances. This is always been a mistake, free Disney inevitable result, selfishness, and now with Material World in death spiral increasingly so.
Life, Joy, is based on the intrinsic exercise of virtue. Always has been, always will be.
Appreciation I think is the resolution to this. In fact one cannot be alive in any reasonable sense of the word without extraordinary appreciation of goodness in nature and in human behavior. Impossible. Inseparable.