The Österreich Rundfahrt already had big problems fiding towns that are willing to pay for stages and a lack of interest from the general public in Austria. Covid was the final nail in it's coffin. Maybe if Konrad and Mühlberger would have lived up to their u23 results and become actual gc riders for gts things could have gone different. Or maybe Austria should have just tried finding it's own version of Roglic among all of it's washed up ski jumpers...
Back to the main topic, there are a few great editions of Tirreno-Adriatico in the last 10 years. 2013, 2019 and 2021 were all great races.
The most underrated one has to be the Tour of Utah. That race always had great routes and delivered.
I've often made fun of the race, like many here, but in 2018 the Tour of Cali was actually really good. The Gibraltar road MTF, the hilly Laguna Seca stage, the over 34km long ITT where Bernal lost the jersey to TJVG and had to attack afterwards and the South Lake Tahoe mountain stage that was an actual mountain stage at altitude and resulted in Bernal destroying his opponents. That was a great short stage race.
I never got into the Tour of California but I feel like that was my loss. It seemed like a great race in another beautiful location. It's a real shame it's no longer on the calendar.