fully agree with the others who have pointed out the many cases where breastfeeding is less convenient, but more practically, one of the most useful baby-hacks in my experience was to put a tiny “skincare fridge” in the baby’s room and put bottles in it overnight (for prepared formula or pumped breast milk)

I don't think that's right (the chart is really misleading - you have to look at bars 3 and 4 as a group, then 5 and 6 as a separate group, then 7 and 8 as a separate group). 

Table 1 in the paper shows the "over-25-male" version: -9% before taxes (row 9), +4% after taxes (row 14)

Table 2 in the paper shows the same for all workers: +2% before taxes (row 9), +15% after taxes (row 14) 

So, a +11pp impact (not -2 as the chart seems to show). 

(Of course, if you're giving credit for increased female earnings, you also probably have to count childcare on the cost side too. If I'm reading Table 3 correctly this won't make a big difference in aggregate, because although the nursery-plus school category has had a high cost increase it's still a very small share of the pie.)