I've unblocked the ways that I could confirm to be ok. Most of the ~1k ways still blocked in Rio Grande do Sul (down from ~6.5k at the flood's peak) are probably open now with varying degrees of trafficability (some of the unpaved may be are prone to getting bogged down due to new soft soil), but to ensure verifiability (https://wiki.openstreetmap.org/wiki/Verifiability), one should not map (block or unblock) ways based only on assumptions. I was unblocking them as I found local photos or aerial footage, since word of mouth (even by authorities) has always been quite unreliable/imprecise here. It may be "safe" (few negative practical consequences in the case of a wrong assumption) to unblock local ways (residential, unclassified, tertiary) where the main ways (secondary, primary, trunk) are known to be ok already. I would be conservative near the river around Lajeado downstream to Vila Mariante which was the most affected area. While we do have an official sources for the conditions of federal and state roads (reliable but often with up to 1km of imprecision), few municipalities are reporting the state of their municipal roads and streets in the detail we need.

The flood took place in early May 2024. What is the date of the GPS traces and the recent Esri World Imagery you mentioned? Can I have a look? I think Strava does not report the date of its data, right?