Bitcoin is showing good and favourable price index. we can expect good results from it in the nearest months coming up.
Why bitcoin over alt coins? Especially considering the transaction and scaling problems of bitcoin.
It's all down to the infrastructure and scaling it to the number of users
- ATMs
- Shops
- Trading
- ICOs
- Mining rigs
- Enhancements (Lightning network, etc.)
- etc. (loads of investors)
As for transactions the price of transactions is dropping rapidly.
As for scalability, Bitcoin is scalable, it only has problems with these stupid-money surges.
As for altcoins, they usually don't bring much to the table and act as an overflow for Bitcoin.
When a Bitcoin surge bogs down Bitcoin people jump onto altcoins....
Just think about Dogecoin in the last Bitcoin 'crash'. Dogecoin was going to be bigger than Bitcoin ... where is it ? nowhere!
Conclusion: Bitcoin will survive
I don't think BTC is scalable especially because of the limited size in the block. This has always been one outstanding challenge for this particular cryptocurrency. However, it's infrastructure and usage as a store of value will continue to provide insight into how other cryptocurrencies emerging as alternate stores of value will operate.