I often read questions about the difference between SMT's and Steem Engine tokens and why we need both.
I made a simple video (in my own way) explaining the difference as best I could.
I am a terrible drawer but I did my best.
Best watched at 1.75x
Conclusion.
The main difference is that SE tokens are on a sidechain and SMT's will be on the Steem mainchain when they come out.
That is a huge difference.
The beautiful thing of a sidechain compared to the mainchain is that updates (hard forks) to the sidechain can be quickly implemented because there is no need for consensus to implement hard forks to make changes.
This results in a very speedy update process for the sidechain but the downside is because there are no witnesses (yet) watching over the hard forks and the code anything can be put into the code and be implemented.
If you want to update (hard fork) anything on the mainchain you have to have the consensus of at least 17 of the top 20 witnesses. They secure the chain and the code but it obviously takes a lot more time to implement changes because of this.
So the difference between SE tokens and SMT's is that anything related to Steem-Engine can be updated really fast but it's less secure than SMT's but updating anything related to SMT's will be a lot slower.
I think there is 100% room for both on Steem depending on the needs of the project/community.
If there are flaws in the video I will correct them.