Paint something with a broad brush
Definition 1 of 1
Pro Tip 1/3Context Matters
The phrase is often used when discussing oversimplifications in complex discussions or debates. 
In the political debate, he painted the opposition with a broad brush, ignoring their varied perspectives.
Pro Tip 2/3Potential Negativity
Using the phrase may imply a critique, suggesting someone is not recognizing subtlety or nuance. 
She painted his views with a broad brush, depicting him as lacking depth.
Pro Tip 3/3Avoid Overuse
Be cautious not to rely on this phrase if you're trying to make precise or thoughtful arguments. 
If you always paint with a broad brush, your analysis may be seen as weak.