This topic has been discussed before in a thread here:
Option 1: Say "Hey we're sorry, but this is the way it has to be. We need to have the starts set up the way they are, because this is the best way to get the elite women ample TV coverage of their race/finish, but we promise to bite the bullet and to continue doubling out the prize money if any women from the mass start posts a net time in the top-15 like we did in this crazy weather year".
Option 2 (preferable): Increase the size of the women's elite field. Add a "sub-elite" women's field that throws an extra 50+ women that get to start 10 meters behind the pro-women's field. These are the 2:40s-2:55+/- qualifiers. They're not going to cause any issues/disruptions to the pro race. They're legitimate racers. This doesn't completely eliminate the possibility of a mass-starter beating an elite starter, but it drastically decreases the chances of that possibility.
What the BAA did: They decided to solve nothing. Instead, they simply ADDED the problem to the men's field so no one could call them sexist.
Now the men have this nonsensical separated start.
So now, in the event that this, or any future year is another freak weather year, and the elite men's field has a ton of dropouts and slow times (2018 Boston Marathon 10th place was a 2:27:50 fyi), those of us 2:18 - low2:20s mass-starters could absolutely pack up and run a slew of times that would put us in the top-15, and then we have every right to be "mad online" about this issue all over again.