A person with TPS benefits may switch jobs at any time. The individual is not required to work and may choose from any employer that will hire. However, there are tradeoffs for giving up H1B visa status.
The H1B potentially provides a path to permanent resident status if the employer is willing to sponsor the employee for a green card. If the individual's goal is to permanently immigrate to the United States, this may be the better option.
TPS is a temporary status that expires at the end of the designated period. DHS may or may not extend this period. If TPS is not extended, the individual must depart the United States. If the individual's goal is short-term employment and to return to a home country, TPS may be a good solution.
Each case is different. Before applying for TPS, the individual should always consult with an experienced immigration attorney who can give the situation more in-depth analysis.