If a parent company that has tracking stock stock becomes worthless, do the shareholders of the tracking stock have claims on assets (e.g. subsidiaries) that the tracking stock tracks? Or is tracking stock just an "illusion" where a collapse of the parent automatically means the collapse of the tracking stock even if the assets that the tracking stocks track are still solvent and profitable?
A bankruptcy means that ownership transfers from stockholders to bondholders. If the value of the assets exceed the money owed to the bondholders, then the excess is distributed to the shareholders. However, that's generally not the case; if it were, the company wouldn't have gone bankrupt. And since your question asks about a case where the parent's stock becomes worthless, we can assume that's not the case. Since bondholders are entitled to the assets of the company, and the subsidiary is an asset, they are entitled to the subsidiary, unless there's some special terms to the bond issue. So if bondholders are owed more than the total assets, they will take all of the subsidiary, leaving no value for holders of the tracking stock.
If tracking stock really is just a no-vote minority exposure to a revenue stream, than the parent company going bankrupt already factors in that revenue stream, and people with actual claims of ownership will already gut the assets for whatever scraps they can find, before anyone with tracking stock gets the dust remaining.
If the tracking stock is really an IPO or direct listing of a subsidiary, and the people own a lot of it, then it can be separate. But then it likely wouldn't be called tracking stock.