I think segwit will improve things as far as the  use goes and the price of Bitcoin will continue to grow.  But I certainly do agree that it is a limited fix and we will run into this issue again in the future unless a better solution is found.  However,  I do not see this as the "failure" of Bitcoin but rather a substantial limiting of it's maximum potential.  Crypto is so strange as it is so extreme.  If Bitcoin stabilizes at around $50K in four years is that a failure?  I guess it is if your goal is 500K in that time frame.  However it is a far cry from 5K which I would be shocked to see four years from now.

That being said, I see the market share of Bitcoin going down surely and steadily.  Name recognition only will take you so far.  As the market matures, so will the people investing in it.  The key is to diversify in good projects.  I think the Bitcoin maximalists are going to be very disappointed.