According to this answer https://hinduism.stackexchange.com/a/44832/22493:
Manu Smriti 5.48. Meat can never be obtained without injury to living creatures, and injury to sentient beings is detrimental to (the attainment of) heavenly bliss; let him therefore shun (the use of) meat.
Why does Manu Smriti state that "meat can never be obtained without injury to living creatures"? What about dying from old age?