Limiting Breastfeeding at 1yr old?

Baby has always been small ( down to the 5th %tile) but by 12 months has now reached the 20th %tile for weight (30%tile for height).

She eats very little; my husband and I are overweight and she's very petite (so not our area of expertise lol). She just wants breastmilk more often than solids (she eats all day, just takes in very little actual solids).

Her doctor told me to limit breastfeeding to just after breakfast so she'll eat solids the rest of the day, and while I refuse a lot of the time during the day so she'll eat something, even just a pouch, she still wants breastmilk after (and will refuse anything else you offer).

Should I really be trying to limit her so much on breastmilk? I know the sites say solids will be her main source of food at this point, but they also say to breastfeed as much as she wants.

It is hell sometimes trying to get her to eat when she has had other food and is just ready for boob. If she is steadily gaining weight (to the point she is increasing in the charts, not just holding steady) should I really worry?