Calculator: https://www.nerdwallet.com/article/travel/how-much-are-my-marriott-bonvoy-points-worth#:~:text=Marriott%20Bonvoy%C2%AE%20points%20are,influence%20our%20evaluations%20or%20ratings.

According to Nerdwallet's calculator, 100K points is worth ~$900...but the trick is you have to stay at Marriotts often enough, and be flexible enough in hotels, that you would use it. So it really depends on your travel habits.

Bonvoy points basically never make sense for my family's vacation travel, but I run a lot of distance races that can be 1-2 hours drive away. I'll use points to book a hotel the night before closer to the race. Since it can take 1-2 hours in traffic to get to my office, I will sometimes also book a nearby hotel the night before with points if I have to be in for an early morning event.

The Bonvoy app is offering me $400 egift to use on upcoming stay (I have one later in the week) + 25k points or the online offer (a la The Points Guy) is $150 credit and 100k points?

The former is tempting but might be shortsighted? FWIW, I was planning to get this card at some point but don't know how long to wait for a better SUB.