It doesn't really matter if they check it or not, I had Nitro for a year during pandemic because I thought I could stream in higher quality. In reality the quality was just as bad, and sometimes video looked very pixelated.

I have gigabit connection at home and a good GPU that does the encoding but I guess Discord doesn't have any servers near me (~1900km to Rotterdam) and it might be prioritizing low latency. The experience was terrible so I cancelled the subscription. All the other paid features seemed useless to me.