Why is my return for 2022 so much smaller than the 2021 return when nothing has really changed in my income and deductions

Without seeing both returns and performing a comparison, I would not be able to even guest what is the difference.  Some laws have changed drastically for tax year 2022 also.

However, TurboTax  has a two year comparison.  The 2-year comparison is in every version of TurboTax if you used the software in the previous year.   To access that just go to the "Search" while in the return and type Two Year Comparison and click on the link.  If that does not work just compare the actual paper documents.

Use this link to see some of the changes that might have affected your 2022 tax return.  Key Changes for your 2022 Taxes

Check these changes

Tax Benefits Changing for Tax Year 2022 - The TurboTax Blog

Why did my refund go down?

https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-refund/refund-go-compared-last-year/L97JmhUbi_US_en_US

2022 refunds might be smaller.  The IRS says....

Refunds may be smaller in 2023. Taxpayers will not receive an additional stimulus payment with a 2023 tax refund because there were no Economic Impact Payments for 2022. In addition, taxpayers who don’t itemize and take the standard deduction, won’t be able to deduct their charitable contributions.

Get Ready now to file your 2022 federal income tax return | Internal Revenue Service

And a couple credits like the EIC and Child Tax Credit went back to the old rules and amounts so you are not getting as much.  2020 & 2021 had special rule changes and higher credits due to the pandemic.