Plenty of ink has been spilled on this forum about the utility of MP letters. The prevailing view seems to be (and common sense suggests), a letter from an MP won't carry much weight unless the MP attests to knowing the spouses personally and can attest to their good character. So, if you have a close friend who is an MP, go for it.
If it works for you, please ask your MP friend to be my friend too.

I am a Canadian citizen and my wife's TRV application was denied in 2020 and again in 2022.