Just a note on the side:
I experience this Bug on android,on switch,on pc.
I also know this Bug since minimum a year. so it is in many versions the same "problem".
When i have a efficiency IV or V pickaxe i still mine in the speed of like efficiency III.
But when i move away from the blocks and start mining outside the block reach distance and walk towards the blocks i want to mine, then it mines at (full speed i suppose?)
else it is VERYSLOW.
Thank you for your report!
We're tracking this issue in MCPE-45619, so this ticket is being resolved and linked as a duplicate.
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