lol. This does not happen, at least not intentionally. PE takeovers are solely about turning companies with a relatively stable revenue stream into a packageable financial product. Huge cuts will be made to staff, support, and R&D to get expenses to a specific level, and large amounts of debt will be taken on under the company's name, to deliver a specific ROI to the PE investors over a relatively short term window of four to five years, all under the assumption that the company will be able to coast for that time on its previous success, after which point it can be sold for IP, trademarks, and any physical plant, or just allowed to go bankrupt under the unsustainable debt load and lack of investment.
That's the purpose of PE firms. They accept pre-investment in this sort of scheme, and do this with several companies at once over a 5-7 year total period, taking a slice of the revenue with no capital risk of their own, and the investors get a good 5-7 years of 12-18% ROI. The companies are trash at the end of the cycle but hey, that's capitalism.
Source: I was "lucky" enough to work for a tech startup through its IPO period after which it was acquired by PE, and exactly the above happened. We had the opportunity to "buy in" to the investment cycle with our own money, and so they had a pretty detailed presentation about exactly how this all works. I was somewhat surprised by how honest they were willing to be with the employees (although it did take a little bit of reading between the lines).