Welcome to the forum! Fireblight is easy to distinguish over other types of diseases. When it kills the tip of a branch it makes a shepherd hook on the end and it looks like it’s been burned with fire hence the name fireblight. Did you spray with copper this year? Fireblight is not match for a spring or fall or both spraying of copper to inhibit bacterial growth. Fireblight is a bacteria. Brings up a good question can other things like vinegar be used since they control bacteria? Keep in mind I have diluted vinegar strongly but its a herbicide so it may do more harm than good so please see this first
Back to your question could the photo below be fireblight yes it could and when in doubt amputate it. Here is the thing could it be roundup or glysophate yes it could
Here is a branch i amputated I just broke it off which as mentioned is how fireblight normally looks. It can on some pears look like the photo you showed. Bartlett is very likely to look like that when infected
My concern is I see no shepherd’s hook in any of the photos which is odd fireblight always does that on at least one branch. Many things like herbicide are possibilities I would look at first. Did the spraying coincide with the trees problems?
