People who find great success almost always have an un-natural obsession or focus on  reaching their goals. It is a fact that a concentrated focus on producing solid results combined with working smart will help to accelerate your success.
So the answer to the question:
"Is it necessary to remain laser focused to find success in network marketing?"
Would have to be...YES! But...
What happens when a network marketer is perceived to be distracted?  What happens when another leader in the company accuses a business builder of being lazy or unprofessional for taking a break or time painting a picture or writing a book?

Is extra attention to family a distraction?  Is expressing your art a distraction?  Is a time for reflection and peace a distraction?
I have heard criticisms by leaders of fellow distributors who are not 100% 24/7 focused on their tasks in Network Marketing.
In fact, I have noticed some people with solid identities prior to entering the industry flounder and dive into a serious identity crisis once they enter the industry and discontinue cultivating their talents outside of NWM.  Some people have been transformed into fully seeing themselves as Network Marketers first and foremost.
I worked as a singer prior to Network Marketing. I love to sing.  I have written books. I love to write.  My husband is an amazing musician.   I have people in my team that are athletes, artists and some continue to be employed in different professions while using their work-at-home businesses as a way to earn extra money.
While laser sharp focus on your NWM business will produce greater results, the definition of success can vary from person to person.
I personally see 'distractions' sometimes as being healthy.  Being a well rounded individual can help to attract a solid and unique team of individuals more equipped to connect with people on the field.
 
We want to be relatable.  We want to connect with people authentically.

So, the next time you hear someone accuse a business builder of 'sleeping on the job' , understand that many people enter the industry to find more time freedom and creative freedom.
Laser sharp focus requires a serious and intense commitment and isn't always fun. People build their businesses at difference paces and we have a right to speed up when we want to or slow down.
Just be aware that major distractions can and will slow down progress. If you desire to crush your goals, you will need to dig in your heels and fight your way to the top with your eyes fully on the prize.
I believe the best Network Marketers are balanced between having a healthy amount of 'distractions' and extra activities outside of their business combined with focused hours working smart inside of their businesses.
The beauty of this business though is that a 2 year commitment and laser focus could yield continual residual income streaming in for years.
The un-natural obsession may be worth it.  But at the end of the day, you are the person who gets to make that judgement call.