It's not the death of open source. It will probably be the death of small company open source. Either 100% community/non profit or 100% big corporation and users check corporate alignment with project goals.
This is not the first small company with a popular opensource project that was acquired. Its not the first time such an acquisition resulted in the shuttering of the flagship product. Its not even the first time the shuttering was announced at acquisition (vs the acquirer letting the product just slowly atrophy away).