Oh ye of little faith.Even these devs could not find a 'bad' way to short my spell fragments. If I could burn/delete them I would. They will NOT stop coming in the Spire.
We've seen it happen with other resources. A few years ago a lot of people "complained" how they always had too many coins and there was no way to get rid of them. People used to be positively angry if they were given a coin rain as an event prize. Then things happened. They developed parts of the game to make coins a much more valuable commodity. I think I would now go so far as to say that the majority of players welcome a coin rain or two, or the ability to increase their output.
That's just an example. It's not just a possibility - it's an inevitability that at some point in the future something will be changed or added which makes spell fragments an important resource in much shorter supply. The more people that bring it up the more that process is accelerated.
I'm not saying the change will be a bad thing. It's good for all in-game resources to be relevant. It is coming, though, and I say it's better to be quietly accumulating as many of them as possible before it hits.