I'd say it has advantages and disadvantages.

One advantage is that whales can't play around with the stock price, say VCs dumping stocks at an unfortunate moment and putting pressure on the price. But it's also just wall street folks doing price manipulation for options schemes that can be an issue (it's illegal but has low enforcement if you are rich and well connected). Also lower chance of activist investors, and less of a quarterly pressure to show nice numbers, etc.

The advantage is also a disadvantage: minority shareholders of non-public companies have much less rights than those of public ones, and that includes employees. That's part of why you are dependent on the founder's goodwill on whether a startup exit can screw over rank and file employees or not. I'm not sure how much that danger is still out there if the company is doing tender offers, but it might still exist actually. Similarly, you can structure tender offers in a way that say former employees are disadvantaged, and many other arbitrary criteria.

Note that this depends greatly on the jurisdiction, e.g. in Germany there is legislation that's unfriendly to minority shareholders even for public companies, e.g. visible in the Varta takeover, imo part of why the idea of adding stocks to pensions will be ripe for money grabbing schemes of whales against the smaller owners.

Also employee of private company with tender offers, but not Stripe. Opinions my own.