An emergency was needed to justify suspending regular congressional procedure in favor of emergency rules in which the speaker could dictate procedure; the speaker took advantage of her power under those emergency rules to do away with the process in which objections to state electoral counts could be heard and debated.

That's why the emergency was needed. So they made one, and a backup (pipe bombs, never used). It's also why Trump delayed his speech so that his people were largely absent when the scheduled emergency ... emerged.