Absolutely. I'm glad she won her seat when she did, but Arizona has changed a lot in two years and there's no reason Democrats need to settle for an ideological outlier. Katie Hobbs, Ruben Gallego, or Greg Stanton should seriously consider a challenge.
The only direct comparison is the House popular vote, which went from D+1.70% to R+0.28%.
Big picture, though: Joe Biden won Arizona, so there's no reason to think Arizona Democrats need to be represented by someone significantly to Biden's right.
To be fair to Sinema, though, I'm not sure she's really "significantly" to Biden's right, and I probably would be okay with her keeping the seat as long as she doesn't screw with the Democrats' national agenda too much. All things being equal, I'd probably prefer Gallego or Stanton, but I don't see Sinema as another Lieberman or anything.