The Rabbis were given a great deal of leeway in protecting the Halachic system. It seems that most of these safeguards translate into stringencies and decrees as the need arises. There is an incorrect perception that the role of the rabbi is to burden the masses with extreme, unnecessary restrictions.
However, there are a number of cases that border on subterfuge when one looks at how far the Rabbis will go to care for the needs of the people.
The selling of Chametz to a gentile is one example of a situation devised by the Rabbis that was meant to prevent a great loss of money. It was originally enacted to benefit Jews that sold alcoholic beverages. It was unreasonable to expect them to discard their valuable merchandise as Pesach approached.
Hillel’s Prozbul was a sort of guarantee to lenders that the Sabbatical year would not be used to avoid paying back loans. Hillel realized that a society must be able to encourage the distribution of loans. Individuals could not be expected to lend money, if they knew they would not be paid back. A major rationale of this enactment came when the Sabbatical year became a rabbinic law after the destruction of the Temple.
The Heter Iska that is mentioned in the Talmud, was a means of avoiding the taking of interest. Israeli banks are supposed to have this document available for their clients to see. This agreement was constructed as a device to share profits rather than charge interest.
And this year a new problem arose because of the Corona Virus. Jews were unable to dip their new utensils in a Mikva, because of the lockdown. The solution the Rabbis proposed was either to set up a quasi Beit Din making all new utensils “Hefker”, or ownerless, or, making some kind of stipulation to be included in the selling of Chametz.
We see from all of this, the sensitivities of the Rabbis to make life more manageable. But we must also remember that this is a situation of, “Don’t try this at home.” This means that only qualified, G-d fearing Rabbis are able to make such adjustments, and they may not be done randomly.
It is always important to see that there are two sides to every story. Great care and an abundance of knowledge is absolutely necessary before making any changes to the Oral Law, or any aspect of Jewish tradition. Judaism does adjust to the times, but it does this without compromising the system taught by G-d to Moses on Mount Sinai.