MC-NSwitch:Wither summoned makes veeeery slow the game

Hola, hello, days ago I fought the Wither and when it reched the half of its life, the game became very slow and lagged, the inventory menu and the cursor were very slow, the L and R buttons to select items in the toolbar were slow, and I forced to reduce the difficult because the blue skulls were destroying blocks and making it more laggy, then when I was hitting the Wither, sometimes it did'nt receive damage or it was  damaged with delay. For me, this isn't normal,  the refrigeration fan of my Switch did'nt turn on, even if were too many entitys like blocks, the itself wither. I will put some videos that evidence the issue, i hope you can solve it 🙂

Video 1: the wither killed me and the game started laggy
Video 2: When I respawn, is normally, but when im near the wither, everything becomes very laggy, slow, isn't the video, is the game, im running and it's like im walking slow, a friend tells me that this is not very Optimized for N Switch