Can you tell me why an efile return would still be pending after 4 days?

The Online fees are to prepare the return whether you efile or print and mail.  

Double check your efile status here     

https://turbotax.intuit.com/tax-tools/efile-status-lookup/   

When you efile you get back 2 emails.  The first email only confirms the transmission.  The second email says if the IRS (or state) Accepted or Rejected your efile.  And check your spam folder for them.

When you log into your account you should also see the status and if it was Accepted or Rejected, Started, Printed, Ready to Mail, etc.  What does it say?

@masterpeeps check closely on what you paid for. 

For federal, there is no charge to efile.  what you are paying for is the tax return output, whether you deliver that via efile or postal service.

for state, you are paying for the software.  there is a charge ($25?), except in NY, to efile. 

see this link for the desktop pricing: 

https://turbotax.intuit.com/desktop-pricing/

see this link for online pricing: 

https://turbotax.intuit.com/personal-taxes/online/live/

First the fees were for the use of the program to complete a federal and state return that can be filed even if you must eventually mail the returns in ... successful efiling is not guaranteed nor is there an extra fee to do so with the online program.

Now as to the pending ... although it is unusual for the returns to stay in a pending status for longer than 48 hours but it can happen.   Log in and check the efile status again.   https://ttlc.intuit.com/turbotax-support/en-us/help-article/internal-revenue-service/find-status-return/L6MXPdusm_US_en_US

After completing the File section and e-filing your tax return you will receive two emails from TurboTax. The first email when your tax return was transmitted and the second email when the tax return has either been accepted or rejected.

Note - Once a tax return has been Accepted by the IRS or a State, TurboTax receives no further information concerning the tax return or the status of any tax refund.  Only the taxpayer listed on the tax return can obtain the status of a tax refund or a tax return.

To check the status of an e-filed return, open up your desktop product or log into your TurboTax Online Account. You can find your status within the TurboTax product.

If accepted by the IRS use the federal tax refund website to check the refund status - https://www.irs.gov/refunds

If accepted by the state use this TurboTax support FAQ to check the state tax refund status - https://ttlc.intuit.com/questions/1899433-how-do-i-track-my-state-refund

Most banks were closed for Juneteenth holiday and processing is behind schedule.