Koinly imported outstanding validator commissions as transactions.

These are generated every ~5 seconds so it imported tens of thousands of unnecessary entries.

It should only import the "Claim" transaction issued once a month, outstanding rewards are held in an escrow address.

As a workaround:

You can filter out by Tag > Is: 'Reward'.

Apply a Bulk Delete on the entries.

Claim Transactions are viewed as plain Deposits.

Apply a Reward Tag on them manually.