Free Step Dodge

Yep... pretty much.

Happens alot in Street Fighter V because the push back is on Steroids.

Technically no, if you throw out a button, you can interrupt your opponent's button if you're fast enough and both can reach each other's hitboxes. However, you won't be able to punish anything otherwise. I personally like to abuse "safe-due-to-pushback" moves. <3 Nightmare.

and if they block then i should just dash up throw/ do another string to keep the pressure up?

They'l lose their advantage if they Dash up...

Hey thats actually worth looking into... see if you can come up with some anti-dash strategies.

I was going to say too that dashing up eliminates your advantage during idle motion/neutral situation. I remember people use to do a jab > short dash > down punch. The short dash ate up your jab advantage and making any follow ups get beaten out because the player took too long to immediately attack after.

If anything, if you are neutral and your distance doesn't cover, I'd jab immediately and then backdash/block.