No, you actually could not. At least not without a huge amount of work, time, and money. If you look at the tree, you will see that his strings have 16 lights each. If you divide that into 500 you get 31 with a remainder of 4 or 30 with a remainder of 20. I would suspect that he has 30 strings of 16 with the remaining 20 being used for the star because even from the distant picture you can see that there are more than 4 lights on the star.
Now here is where the problem is. If the smartstring nodes that we will be using are 3.5 inches center to center, then a string of 16 nodes would only be 56 inches long. Considering that the strings will be on an angle would max out the tree height at around 52 inches tall (not including the star). A 5 foot tall tree (including the star) is not much of a megatree. Looking at the vid, I would say that his lights are around 8 to 12 inches apart on the string making the string lengths anywhere from 10 to 16 feet long which is well within the megatree range.
If you wanted to make a megatree using 12 foot smartstrings and keep that string count of 30 then each string would have 41 nodes which would total out to 1230 and this once again does not include the star. If you wanted to do it with 500 nodes on smartstring, you would have to increase the distance between the nodes and that's 6 connections and 6 inches or more of wire between each node. That would be 2880 connections and 240 or more feet of wire. Add in the time, solder, and shrink tubing and as I said, $$$$$$$.
