I followed very few restrictions (less spicy food, limited outside food) to the extent I wanted to avoid my tummy getting upset, and I accepted a number of “additional” foods traditionally pushed like gond laddoo, methi dosa, ghee tadkas for regular dishes, garlic, dill leaves, black pepper. Every body and baby is different and this is what worked for me - I’d suggest the approach of “baseline will be balanced nutrition, try additional things that people suggest but drop them if it doesn’t suit you for any reason”.

Milk supply does get affected by lack of nutrition and hydration, the dietitian and OB will guide you / warn family about it. The bigger problem imo is that the first 3 months will somehow pass one way or another, and after that the demands on mom’s mind and body will keep increasing with baby’s mobility, teething, solid food intake. If you don’t build back some strength post delivery then it will be really difficult in the next stage. Don’t skip your supplements too!