No, an engineer without a Professional Engineer license is not "cutting corners". They most likely just don't do the type of work that requires getting a PE.
The article says 80% of engineers are working without a license. From experience, this is especially true for electrical engineering. Someone designing a building's electrical system would have a PE to sign off on plans (or be working under someone with a PE). But someone doing embedded design would not, because there is a completely different approval process for consumer/industrial products - we test rather than simply asserting products are safe because they were designed by a PE.
Without a PE, I am still an engineer. I can say I am an engineer, because "engineer" is not a protected title anywhere in the US. I can speak authoritatively on engineering topics, because I have vast technical knowledge. My opinions on topics I know little about (eg civil engineering) will be tempered with "I think", because knowing one area really well, I am aware of how much I do not know in other areas. Whether anyone chooses to listen to anything I say is their own choice.
What I cannot do is sign off on plans for permits, solicit business that would generally require signing off on plans for permits, or anything else that specifically requires a PE license. Those requirements are in legal force due to the product delivered (eg a bridge requisitioned by the state, a house which needs a building permit) and are not generally applicable for all engineering activity.
There also is the related issue that everybody has the right to technically criticize a situation if they have done the work to make their case. Only a licensed Professional Engineer has the ability to say a bridge is safe, but we all have the right to claim that it is unsafe.