Nasrallah needs to show solidarity with Hamas, in part to ensure a continued flow of funding from Iran. However, Lebanon cannot handle another war, and the other political factions have already been pressuring Hezbollah to not escalate.
Israeli leadership seems to want to go after Hezbollah, but have been warned off by international pressure to not open a second front. This is the other half of Biden’s “don’t”. It’s a warning to Israel to keep the conflict contained.
Ultimately though, Hezbollah are willing and able to go tit for tat. So long as Israel continues to kill off firing teams, Hezbollah will feel obligated to respond. Hamas do have some forces in Lebanon and will attempt to draw Hezbollah into the conflict as they have in the past. So the northern front will continue to simmer with a few casualties daily until the war ends. Or I could be wrong and it will either go fully quiet or fully open.