It seems to me that altcoins have even a greater future than bitcoin because the only benefit of the btc in its price, the altcoins, however, are more technologically and more functional.
Yes, you are right. I also suppose in future even faster, safer and more anonymous altcoins will appear and replace some of coins used on the cryptomarket now. Sure alts will survive and will be used.
The new technology will replace the old technology as long as new technology is better than and useful more than old technology with many problems. Bitcoin is an old system, if it doesn't improve its system while the time confirmation and fees are the problems, it will be worse than Ethereum and Ripple soon.