The fact that bitcoin is not controlled by anyone or a company, that is more than enough why people have full trust towards bitcoin and majority are considering bitcoin as the bases value of most of the altcoins in the market today.
And, Despite the fact of it's scalability imperfections, this doesn't stop people from using bitcoin even if there are alts created to fix the scalability issues of bitcoin, but because they are run by a group of people, this has created a huge difference against bitcoin.