Gov. Gavin Newsom of California on Sunday described the new pandemic plan he released last week as a “more sensible and sustainable” approach that would lead the state out of “crisis mode” now that Omicron cases had dropped significantly and many residents were eager to move on.

His comments on MSNBC followed an announcement from state officials last week about a “next-phase” plan, which would prioritize strategies like coronavirus vaccination and stockpiling supplies while easing away from emergency response measures like mask mandates.

“A year and a half, two years ago, we had a war metaphor and we were hoping there would be a day where there would be a ticker-tape parade à la World War II,” Governor Newsom said. “At the end of the day, though, I think we are realizing that we’re going to have to live with different variants and this disease for many, many years. And that’s what this plan does, it sets out a course to do it sustainably.”

The Omicron variant sparked an enormous surge in California. Though the state has seen a sharp decline in known infections since mid-January, new cases are still hovering at more than 13,000 per day. Overall through the pandemic, the coronavirus has infected at least 1 in 5 Californians and killed more than 84,000, according to a New York Times database.

California is among the many states to loosen masking requirements in recent weeks, with Hawaii as the last state holding onto a statewide mandate. Puerto Rico also has yet to announce upcoming changes.

But federal health officials have yet to release any new recommendations that reflect the lifting of restrictions — including mask mandates in schools — in nearly every state, and the U.S. path in the next phase remains complicated.

Dr. Rochelle Walensky, the director of the Centers for Disease Control and Prevention, last week cited the need to “remain vigilant” so that infections continue their promising decline nationwide. She said the C.D.C. would soon be releasing new “relevant” guidelines that would suggest adjusting restrictions, including for mask-wearing, based on factors like hospital capacity, not just case counts.

Despite the rollbacks across the country, many people remain extremely vulnerable and feel left behind by the changes. More than seven million adults in the United States are considered to be immunocompromised, meaning they have diseases or are receiving treatments like chemotherapy that reduce their ability to fight coronavirus infections or respond well to vaccines. And tens of millions have other conditions that put them at greater risk for severe illness or death.

California’s new plan emphasizes surveillance and preparedness, focusing on continuing to promote vaccines while stockpiling medical supplies, ensuring surge staffing, combating disinformation and increasing wastewater and genomic tracking to spot new variants. Under the plan, mask requirements would be subject to change based on the severity and volume of new infections.

In his remarks on MSNBC, Mr. Newsom acknowledged the fatigue felt by people because of the “whipsaw component” of changing rules and policies depending on each surge or wave. “We’re exhausted. Everybody is exhausted. And at the same time we’re also a little bit anxious. What does the future hold?” he said.

California’s new policy was based on a two-month review of best practices across the world, Mr. Newsom said. But he stressed the need to be “humble” in the face of a virus that could continue to mutate in unexpected ways.

On CNN on Sunday, Gov. Jared Polis of Colorado also emphasized the uncertainty of what could be around the corner, even though he had lifted mask mandates and other restrictions last summer. Asked why more governors were doing so now, he highlighted the protection now offered by booster shots, which dramatically decrease the risk of severe illness.

California and Colorado have reported a fully vaccinated rate of about 70 percent; roughly 92 percent of Colorado residents 65 and older are fully vaccinated, as compared to 89 percent in California.

“I think what’s important is we prepare for an uncertain future,” Governor Polis said. “And I think a lot of states are undertaking that. I hope the federal government is as well.”