Evidence of what?
I am giving you an example of a scenario that could sway the support of these truckers. It isn't like I am coming up with crazy hypotheticals.
Optics matter for a protest and waiting for something bad to happen because you don't want to play what-if considerations is reckless for the cause of a protest. If a building burned down because trucks wouldn't/couldn't let through a fire truck then it is already too late. Truckers can't just say "we will come up with a plan to not let this happen again" and everyone will be happy with them again.
We have entire groups in the military dedicated to "what-if" scenarios. You telling me truckers can't bother to consider what if their blockade lead to a loss of support for their cause?
You're saying everyone needs to put the same effort into planning their protests as military doctrine planners and researchers?
What planet are you on? You really ought to stop using anything military-related in your comments since you don't have the experience or facts to properly apply those concepts.
How many protest planners have first aid kits, water stations, and "lost & found" baskets? How many pay for ambulances and fire trucks to be on standby in their protest area? How many have cafeterias set up to feed the protestors?
Protests are not like marathons and other public events. They are voluntary, and any consequences of being there are accepted as part of the risk of attending.
As for public services being able to reach non-participants in need, that can happen with any large event -- imagine the traffic after a sporting event, political rally (Obama's or Trump's, not Biden's or Clinton's!), a fireworks show on the 4th of July, or even after a popular concert lets out. Often the local LE send patrol cars to help direct the traffic and keep it moving. Seems like that's where the responsibility lies -- local officials with the resources and duty to protect the public at large.
So, don't blame the protestors if something they could not predict happens. They can't be expected to plan for every contingency and hypothetical and have procedures and resources stationed in the area to handle them IF they even occur. These are not an organized government-funded entity with training and a mandate to protect life and public safety. They are TRUCKERS.
Some jurisdictions require a permit for public gatherings, including protests. The permits lay out requirements, many of which might address some concerns you have such as blocking streets. Sounds good, except we saw where Dem-run cities ignored the permit requirements for Leftist organizations, but charged money for, and even in some instances REVOKED permits, for Right-leaning causes.
It's ridiculous to expect people to protest with permits if the people issuing them favor some protests and not others.