Explain how Roche's in-the-money Bull Spread put options with a strike price of SFr 7,000 were equivalent to fixed interest-earning securities

Why might investors be more interested in owning securities with put options than owning interest-earning securities having identical rates of return? Why might the Swiss government object to the issuance of securities with in-the-money put options?

The put options gave investors the right, but not the obligation, to sell 100 warrants and receive SFr 7,000 . Because each warrant was worth SFr 66.21, the value of 100 warrants
at inception was SFr 6,621 . Roche was guaranteeing investors at least a minimum return of SFr 379, which is equal to a 1.9% annual internal rate of return (IRR) for three years.
The benefit of earning warrant-related returns is that they are often classified as capital gains and taxed at a rate lower than the rates on ordinary income. Because they reduced Switzerland's tax base, the Swiss government cracked down on put options that guaranteed such returns.