It's definitely an assertion. Actually, there are 3 reasons to do 22.8888

• protect the network
• revenge
• protect the price

The only one I think is unnecessary is to protect the network. If they are able to get >50%, technically choosing witnesses is their right. Justin has accepted the freezing of funds and censorship on Steem post 22.8888 so he cannot exactly be opposed to whoever has a consensus doing it. However, it's extremely doubtful they could get close to this since they were unable to between 22.5 and 22.8888 and have started power downs.

Doing it for revenge is understandable, but petty.
Doing it to protect the price makes sense. In the long run, it actually doesn't hurt if the price decreases because it allows people to sell who want out and people to buy who want in. The price can go up later and Justin promised to use Tron resources to help develop in the meantime.
That said I hope their accounts are unfrozen soon, no matter how you look at things, it's their Steem to sell. It would be ironic if the price went up a lot in the meantime and this ended up making them a ton more money from HODLing.