There are a couple of subtlies to get straight here.
One is an assumed definition of "progression". If we think that bigger, smarter, faster, or whatever else is "better" then we might see progression.
However, in evolutionary theory there is only relativly more able to survive at a given time, in a given enviroment. Bigger is not always better, faster is not always an advantage and it's not clear that smarter is either.
Second is looking at a very selective portion of all living things and looking at the result of the evolutionary pathways.
Today after 3.5 Gyrs of evolutionary change life is still overwhelmingly bacterial or simpler. By mass, individual count, number of species or any other measure of surviving succcess you want to use it is, as Gould says in "Full House" the Age of Bacteria. Always has been always will be.
The rest of life is just a minor statistical bump on the charts. There has been, at most, a small amount of "progress" if you carefully define progress to be less bacterial.
What we do have is a movement in the [b]maximum[b/] size, complexity or what have you. While the average creature is still a bacterium the most -- whatever you pick -- is not still at the bacterium level.
As is also described in "Full House". If life started at the stage of about a bacterium then it almost has to move the average and certainly the most "complex" somewhat away from that. The only other direction to move in would be total extincition.
In the example given if what we call intelligence is defined as being "progression" then there has been progression. But that is just an historical accident. Evolution happened to take one branch of life through a rapid increase in brain size and intelligence. That worked for those forms of life. It would not be progression in a lot of environments that couldn't support a large, expensive brain.
It may yet prove to be a dead end.
If you stand back and look over the entire evolutionary history of life you will see lots of different branches moving in lots of different directions. Most have stayed near the base (almost all in fact). A few have moved a bit farther from that base and maybe temporarily farther.
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