Wither fight switch two beta

I set Minecraft to be set for optimal performance. I spawned a wither and in the second half of the fight when more blocks were destroyed, the game became unresponsive. The frame rate dropped to below 10 frames per second and I could not see what was going on. I could hear the Wither attack and that I received damage. I could hear my character walking around when I tried to move but could not see much. Occasionally, I would see dozens of dropped blocks, which then disappeared again. Eventually, my character died. The experience was similar to the wither fight on the original switch.