My brother and I have been experiencing the same issue with our switch worlds. I also will lag even in single player, but it at times unbearable in multiplayer. My son died in hardcore in my world due to lag. To the point we had to start multiple hardcore worlds. never had this issue until the latest update to minecraft. It is to the point we may stop playing until the next update in hopes it fixes the lag.
In addition to experiencing this, i have also experienced getting kicked from the world my brother is hosting on his switch when the issue above happens. very annoying to play minecraft like this
My brother and I have been experiencing the same issue with our switch worlds. I also will lag even in single player, but it at times unbearable in multiplayer. My son died in hardcore in my world due to lag. To the point we had to start multiple hardcore worlds. never had this issue until the latest update to minecraft. It is to the point we may stop playing until the next update in hopes it fixes the lag.