Not an employer. But I believe most employees simply put in less hours when working from home, and most employers aren't very good at rewarding people for their results, not their hours.
Like maybe I go afk 30-45 mins here or there when I normally wouldn't in office. But for me, I put in more hours overall. A key to this was learning to not have my personal laptop open to the side, and avoiding distractions like social media and idle browsing.
YMMV of course, I think it can really depend on the person and their life situation. But the same could be said of anyone remote or not when it comes to productivity. It's on the managers to measure if things are getting done or not, which is the most important thing.
Common counter argument to this is that the manager sucks because he/she can't measure the work otherwise. But from managers perspective it is much easier to force people to be on-site than fix his/her own problems.
They also mentioned avoiding other distractions: That's the main feature of remote for me, after many years of wearing headphones all day in various offices.
Because if they're not, they miss deadlines.
Of course, employers want both butt-in-chair metrics and 24/7 availability without increasing pay. Don't give them that.
What do you have to back up your belief? I work from 8-6 on most days +/- 30 minutes. Lunch is a walk downstairs, grab something and eat it at my desk. That's pretty typical of the group of engineers I've been working with remotely on/off for the past 15 years. I don't think we're exceptional in this regard.
Plenty of people with one job don't perform and get cut. I've worked with people in the past who I knew had multiple FT jobs, or a FT job and a very demanding contracting schedule, or whatever, and had no trouble doing their work in a reasonable timeframe.
This whole idea that it's wrong or bad to have two FT jobs just smells like some middle manager feeling like they "own" their employees. I'm glad to see the culture has shifted somewhat and people are starting to see how ridiculous that mindset is.
From my experience and observations I've gathered from my teams, my conclusion is the opposite of this. I have to regularly tell folks to watch out for burnout and it's ok to wait until Monday.