You mean if somebody targets low comp keywords it possible? Or without backlinks impossible to target low comp keywords too?
Comparing keywords on just number of monthly searches - not giving any real picture of situation.
For example:
Long tail KW containing "free wallpapers" with 100 searches per month.
Long tail KW containing "luxury cars" with 100 searches per month.
Now let's think, how much money you can earn with just 1% of conversion.
In first example it could be just 1$
In second example it could be $10 000
The only real picture of situation you will get by checking BL.
Without Ahrefs or Majestic - you are not able to compare competition in both cases with same number of monthly searches.
So, many people have just an illusion about "simple keyword" when they not using any BL tool.
As the result, they haven't any chance to get high position in Google.
Especially when they comparing stupid metrics such DR or DA.
And usually they are talking "It's definitely impossible"
Cheers, Greg.