Engines with lack bottom end power?

Now I am just spitballing here and of course there are a lot of factors involved besides this but wouldn't port velocity have something to do with it as well. I don't know if you have done significant porting and polishing but once you open up your ports significantly, wouldn't that slow down your port velocity down low (less than 2500 rpm) and in turn make your engine feel like a little sluggish. But as you begin to go up in your rpm range and you start getting the airflow to fill out your intake runners/ports as well as get into the ideal range for a larger cam the engine should really come alive (3000rpm +?)
In this case a "stock" engine (318,360,/6) having the small stock sized ports and intake runners would in theory have higher port velocity down low to take off from stop in 3rd gear but quickly run out of air in the higher ranges of the rpm range...
I might have explained myself a little wrong but I think my concept is correct?