If you aren't particularly big or heavy, then 125 grams of protein is a decent quantity. Guidelines generally suggest 1g/kg of body weight daily, and for those shedding pounds with GLP medications, 1.5g/kg of ideal body weight each day. So unless your ideal body weight exceeds 83kg — which could happen if you're tall and muscular, though it's not very probable — you're meeting your protein needs. As for the proof behind eating more protein, it isn't exactly conclusive; anything above 1g/kg/day is likely sufficient. Does consuming the bulk of it at breakfast mean some is wasted? Possibly? Your body simply breaks protein down and turns it into amino acids, then further degrades them to supply energy; they can't truly be stockpiled except through building additional tissue or muscle. However, your body can produce most amino acids as needed, apart from the essential ones, since humans have lost the enzymes required to synthesise those.
From my perspective, your method is actually great for keeping hunger in check throughout the day. A large protein hit like that in the morning will curb hunger for several hours (equivalent to 375g of lean meat), far more than other calories would, and you get the added benefit that 20% of the calories in those 75g of protein are burned up during protein metabolism. So rather than 75 x 4 kcal/g = 300 kcal, you're left with 240 kcal, and you get to consume a bonus 60 calories that don't count metabolically. If you'd prefer to feel hungrier during the day, then having less protein in the morning might do it, but typically when you're trying to lose weight, you want as little hunger as possible.