These seem very sensible proposals to me. e.g., Toys R Us was a perfectly viable business, if not for the ridiculous debt-load. Thousands of low-paid workers lost their jobs, so that some PE partner could make a few million bucks.
Thousands of workers lost jobs because the company leadership and market pressures crushed the company; oh, and that debt.
Enter PE and a much needed restructuring. Now Toys R Us is reformed into more of an experience vice pure retailer. [2]
While not as large as it once was there are jobs there now whereas absent the reforms PE brought there would very likely be only some real estate for sale and a footnote in business history. And no jobs.
So yeah, blame PE.
[1] https://www.retaildive.com/news/inside-the-20-year-decline-o...
[2] https://www.cnbc.com/2019/02/11/toys-r-us-executives-plot-re...
The article [1], rather, seems to present the 2005 buyout as the terminal blow to a weak company; it was only after 2005 that maintenance of the physical stores was neglected.
Also, it's not clear how the specific reforms proposed by Warren prevent restructuring and changes in management.