Just like Microstrategy, tether is planing to be investing more on bitcoin. But unlike Microstrategy, we do not know how bitcoin maximalist they are yet.
One thing i also believe is that not only tether is into this, there are many other companies and organizations that do buy and hodl bitcoin consistently without us knowing as long as they are not making noise about it, this are investors that don't only rely on their own coin, they uses other's invest with them to secure a guaranteed asset with bitcoin in case of times of uncertainties.
One thing to learn from is that they stated that they are putting their bitcoin holding into a self-custody wallet.
They all invest with bitcoin and have their coin in their personal wallet while their own investors will have theirs with them, what an irony.