100% agree, ETH is dead so you won't be able to move that ASIC to different algo, maybe ETC but that's all. You do loose flexibility.
The problem is not actually moving to a different algorithm. The value of the equipment is the issue.
GPU mining is usually a safer investment when it comes to capital cost, because video cards are very reliable (1-3% failure rate, 2-3 year warranty) and they have a robust gaming resale market.
ASIC mining is safer in terms of predicting revenue (BTC difficulty & price moves slowly), but the hardware is much more faulty and power cost is very important. If BTC price drops by half, the equipment value can go down by 3-4x.
Here, we're talking about an entire coin getting eliminated and the second-best one, ETC, having 5% of the market cap. The ETH ASICs could be completely worthless. They offer no advantage in profit over GPU rigs. The Innosilicon A10 is the worst of both worlds!