This one reminds me a little of something I wrote a few months ago, but the topic is slightly different: https://steemit.com/steem/@abh12345/am-i-stupid
My take is that we have been 'battle-testing' the technology, but that's pretty cool right? And it's made some people a lot of money.
Steemit will still be here, and you will find the same people through other windows into Steem, just like with busy.org and esteem at present.
It's also likely that your friends and communities will meet on other sites using the SMTs. And with Communities, this should be even easier and (hopefully) negate the 'need' for 'the double-edged discord sword'.
Fearing change is natural, but there is a plan and IF it works, good times are ahead.
People will come and go, but it wont be because steemit.com isn't here, it will likely remain as the premier front end to Steem.