In the video on Lebanese TV a few days before Nasrallah was killed by Israeli bombs, Shiite cleric Mohammad Ali Al-Husseini told Nasrallah:
“Write your will. The Iranians betrayed you".
Most people have no idea how the ME really works and what the prevailing strategy and thinking is among Arab nations.
Basically, it's like this:
Israel has nukes, so has a strong hand in the region. At the same time, it is not a major nation, with just 6-7 million Jews in Israel and a further 14 million scattered around the world.
Israel therefore lacks the kind of natural global power and influence that major nations have. To compensate for this, it has developed a widespread intelligence network in many countries, particularly in the major global powers. It uses this network to influence, to spy, manipulate, blackmail and influence these nations in Israel's favor.
What is "in Israels' favor"? Israel wants to be the unchallenged major economic and military power in the ME region. The US and UK (in particular) also want this, because through it they can better control the ME.
To achieve this, Israel needs all resistance, both military and ideological, to it to be wiped out.
But Major ME states are disinclined to allow Israel (and by extension the US and UK) to have this level of control.
So while ME powers are wary of provoking Israel too much to the point they would ignite a major war in the ME to the detriment of all ME Arab nations, they allow the "resistance" (primarily Palestinian and Hezbollah) to continue to 'harass' Israel by supplying the resistance with funds and weapons.
This is to remind Israel that it cannot have everything its own way, and ultimately it will have to accept a position in the ME that is consistent with its *actual* power status (GDP, population etc.) in the ME.
So a delicate balancing act is necessary, and those individuals or groups in the Arab "resistance" that, at times, by accrue too much power to themselves and make plans to take things too far with Israel must be reigned in, primarily by the major ME nations, primarily Iran, but also the Gulf states and Egypt.
Reigning in such individuals and groups includes, at times, the need to facilitate their removal by Israel or the US through supplying information to Israel.
This was the case with Soleimani a few years ago, and also the case with Nasrallah more recently.
This perspective is one that Western supporters of the militant Arab "resistance" are very reluctant to accept, but great power politics does not function primarily on the basis of hard core ideology but real world practicality.
Also, Iran has nukes.