IMO it l it's a wasteful use of a scarce resource that affects users trying to make actual transactions.
A simple transaction is sending money from A to B.
A whirlpool transaction or similar is sending money from a bunch of As to Bs, still valid.
An ordinal transaction is sending a few sats to yourself with a bunch of BS non-financial data attached that fills up block space and places a burden on node operators and other network users. That's spam.
