Yes, the reverse of that truth is actually very useful. That's exactly what the Four Noble Truths come from: in order to end something we must understand its beginnings.
But let's analyze it in detail.
First of all, the original saying in Buddha-Dharma is not exactly "Everything that has a beginning must have an end". The original saying uses slightly different words, it seems similar on the surface but has a rather different meaning in depth.
The original is,
yaṃ kiñci samudayadhammaṃ, sabbaṃ taṃ nirodhadhamman'ti
SN 35.74
or
"whatever has a nature of samudaya -- all that has a nature of nirodha"
Samudaya is from sam + ud + i, literally “together + up + go”. It has a meaning of composition, coincidence, junction, i.e. an emergent effect of multiple causes and conditions coming together. Also the meaning of Samudaya is not confined to momentary beginning, it's more like sourcing or continuous generation. Consider a fire that keeps generating the heat as long as the firewood remains together.
Nirodha is NOT an antonym of samudaya, it does not imply falling apart! Instead, it comes from ni + rodha, literally "no + fence". It has a meaning of arresting, blocking, suppressing, preventing, confining, i.e. not letting something harmful to come and get us.
So the meaning of the saying is: all phenomena produced from combinations of causes and conditions can be stopped and prevented. And of course the phenomena we are talking about are various kinds of dukkha and it's predecessors or precursors: conflicts, wars, misunderstandings, diseases, pandemics, the global warming and so on.
If we try to reverse this truth, by starting with Nirodha and going back, we can say: look, we have this phenomenon that we want to stop, and we don't want a new one like this to arise again in the future, how can we do that? And looking backward to its Samudaya we can say: let's try and understand the composition of this phenomenon, what causes and conditions it comes from. Then, once we find the necessary conditions, we can say: removing these conditions will stop and prevent arising of the phenomenon. And then we can come up with a methodical plan for doing that.
Reminds of anything? Of course, because these are the Four Noble Truths! Turns out, they are based on this very principle: in order to nirodha something we must understand its samudaya.
There are two famous sayings in Buddha-Dharma:
- "All composed phenomena are impermanent."
- "Whatever comes together can be stopped and prevented."
— These are two sides of the same coin. The first one is the passive outlook where we find ourselves as the victims of the cosmic order. The other one is the active outlook of someone ready to be the master of his or her destiny.