It's not just TurboTax.
I filed a paper return at the beginning of May. It's August now, and my "Where's My Refund" shows nothing, and "View My Account" > "Get Transcript" on the IRS web site says there is a Verification of Non-Filing letter available for 2020. I have tracking confirmation from the US Post Office that my return was delivered to the IRS, but I never received the green return receipt postcard.
I also filed some late returns for previous years in April (all of them due refunds, so no penalties to worry about), and I have the green return receipt postcards for all of them, but they all have Verification of Non-Filing letters, too.
Yes, everything is processed more slowly when it's filed on paper, but even allowing for that, the IRS is WAAYYYY behind. State of California processed all of my returns within a couple of weeks of my mailing them.
