Over the last 20 years average home price in Utah has increased ~6%/year, ~9.7%/year over the last 10 years. S&P500 over those two periods has averaged 2-3%/year more than home prices in Utah. It's anyone's guess as to what the markets will bring, real-estate performance can vary significantly within a state. Right now you have leverage amplifying your gain/loss potential compared to just investing the sale proceeds.
mortgage + repairs would wash out most of the rental income
That doesn't mean the only benefit you get is from increase in property value, you're getting equity every month by someone else paying the mortgage. Similarly, if the value continues to increase so too will your rent, which should increase cash flow. You'll want to properly calculate your ROI as part of your decision. I suggest setting up a spreadsheet and forecasting a few scenarios for each (historical average, optimistic, pessimistic) and compare that way.
Ultimately it depends on your preferences and outlook. If you like being a landlord well enough and you think home prices won't grossly underperform the stock market then being leveraged at a low interest rate could work out very well. If you are wanting to sell anyway and think real estate will underperform then you should sell.
Personally, I like being a landlord and view it as a form of diversification since my 401k/IRA/brokerage accounts are pretty much all stocks/options, but it's not for everyone and certainly not guaranteed to be profitable.