I have found the Create Synonym process is truncating long object names allowed in more current Oracle releases. I am using Oracle 19 and here is a long View Name:
Here is what I get when using Create Synonym Wizard as a user on the same Oracle 19 instance to create a Synonym for that View:
Note that the name is truncated in both the Create Synonym GUI Wizard right hand pane as well as in the Generated SQL. This is a low priority issue as manually creating Synonyms is very simple. As this is the second place I have found issues where TOAD processes have issues with long object names, you may want to have support run through your create/modify GUI Wizards against objects that have Long Names.