Dalbec is not "becoming an offensive liability." He's one of our hottest hitters. I agree he struggles vs RHP, so a platoon might be best. Duran and Arroyo won't help with that. Dalbec has 3 2Bs & 3 HRs (some huge ones) in his last 8 games. His OPS over that time is 1.149 (10 RBI).
Chavis only has had 3 looks- one during COVID season.This look, he has done pretty good in just 31 PAs (4 2B & 1 HR) with an .806 OPS. He has a career .732 OPS in 571 PAs with 24 HRs. That's a good enough start to a career to get another or longer look.
I'm not against bringing up Duran. His bat certainly looks ML ready, and maybe if his glove isn't, it might still be worth it. Bringing him up sure looks like it makes sense. If he can play CF FT, we can use Hernandez or Santana to platoon in LF when Verdugo plays RF vs RHPs and Renfroe sist vs righties. Kike can play 2B with Arroyo. Santana can platoon with Dalbec at 1B. That does leave Chavis as a 3rd stringer at 1B and 2B, so I can see why he would be the choice for Duran, but I think he deserves a longer look.
Keeping Duran down so Chavis gets a longer look sounds dumb, I agree, and he'll likely get another chance at some point due to an injury, so when Duran is deemed ready by Bloom & Co., I'd have no issue with Chavis being sent down. There really is no other option barring a trade of Santana or Marwin, which I seriously doubt is even being considered.
Santana won't be sent down, soon.