I've seen guys use spikes like those but don't think they are the best tree steps for sure. Also, it would be much better to pull those buggers after every season. Yet, I have 2 or 3 trees that I forgot to pull steps from and they've grown right into the trees.
This is Ironwood on a TSI, Timber Stand Improvement job I did. The forester that marked the trees said these two were the biggest in the County, they normally don't get real big. One was so rotten I stuck the bar making the FIRST cut of the face.
Not giant as trees go, but knowing the forester said it was the biggest around, it made me smile to cut it down. Two things,: I have never seen sap run out of tree like the Ironwood did when cut. The one was hollow and literally many gallons of water ran out when the face was put in.