Their music made such an impact. They had so many songs that helped so many through so many things. (how many times can you use 'so many' in a sentence?

)
It's frickin' great music song by people who could actually sing. They didn't sing about bad stuff, if you will. Their music is uplifing, sung by great singers, put to great music and it tells a story about what means the most to us. Those two groups, especially Dennis' Styx songs really hit the nail on the head. Dennis songs told such a story about things we could relate to.
There is such passion in Dennis' words and Steve's voice, that it's hard to not be passionate about them. Their songs hit the core of our souls and heart in every way. You put that to great music and voices and it just cannot be helped.
I also believe that more passion came once Dennis and Steve were gone because of who they are, what they represent and how they sing.
Maybe Styx and Journey fans are just more vocal about their opinions so it seems that they are more passionate-

J/K!
and........, who hasn't made out to a Styx or Journey ballad?!
Who hasn't had a song from one of them help them out at one time or another through a bad spot, or a good one.
For ME, uplifting, great singer, great music, impacting, timeline, story telling, etc... are the words that come to mind.