I seriously doubt if there is any Buddhist 'investment' that is meant to be and can be reaped to begin with RajeshA garu.
Buddhism has two aspects. The spiritual structure and the socio-political ideology.
1/ What we exported was the spiritual Buddhism. There was no socio-political export that is available to reap benefit from. That is why none of the Buddhist nations find any socio-political affiliation with Bharat and were able to form independent national policies.
I think here you're mistaken!
What does the West have in common? What does all the Islamic countries have in common? They all have the civilizational glue, and what they have learned is that the victory of one country belonging to their civilization over one of some other civilization is a benefit for their whole civilization.
We have not learned these lessons! In fact at some time we knew these lessons but have forgotten them - Sabhyata over everything else!
We may have exported spiritual Buddhism but where ever Buddhism took root it established its own sociopolitical structure there with its own cultural nuances. Often Buddhism was the official religion in these countries, stretching from Myanmar all the way to Japan.
It is fully okay for each nation to have its own Buddhism variant with nuances. It is fully okay for them to be independent of Bharat.
There is no compulsion on each and every Buddhist nation to receive its political directives from Magadh. What is important is that all see themselves as connected, belonging to the same civilization, that they prosper together and come to the aid of others, when other civilizations wish to prey upon them.
Only the Chinese model requires a single political center. Islam is based upon fragmented political actors but a single political ideology. West is based upon hidden white supremacism, and thus interests of a single race led by the strongest among them. West too allows multiple nations within it.
What the others expect of Bharat is not political domination of the others but spiritual and ethical leadership and civilizational defense
! This has not been forthcoming from Bharat for over a thousand years now, and many have thus left the civilizational umbrella and looked elsewhere like Indonesia and Malaysia.
But an Indian would still receive respect everywhere where Buddhism has left an imprint and where the Western narrative has not buried it.
From Mongolia to Myamar people look towards Bharat and are disgusted to see their "mother civilization" totally deprived of it!
The spiritual structure that exported in the name of Buddhism is adulterated version of SD. That is why Bharat proper did not feel any loss when it got rid of Buddhism.
I think it is wrong to see it this way. Bharatiya Sanskriti is a knowledge tree and it would naturally grow with different sampradayas and philosophies emerging from what there is before. Why should something be static? The search for Truth cannot be seen as completed!
As long Dharma, especially Raj Dharma is taken care of, any Dharmic Sampradayik evolution is acceptable or replaceable.
Please note that entire societies and regions were converted to Buddhism before they reverted back to Hinduism, for they realized there is no spiritual value in that system for the socio-political price it demanded. This experimentation however hurt Bharatiya interests immensely for it weakened the system to the core and left its traces all over even after the society reverted back to Hinduism.
It did not really matter which mata मत
really had the upper hand in some Indian kingdom as long as the king looked at it from PoV of Raj Dharma, equal treatment of all, equal protection to all and was aggressive about defense. If the King did not act accordingly then he was useless.
The system became weak because of religious identity politics and mercantile interests, but it did not necessarily have to do with Buddhism.
Pitting Buddhism against Hinduism makes zero strategic sense, even from the point of view of historical analysis and revisionism.
2/ What we internally have is the socio-political Buddhism. Internally Buddhism cannot be an unifying factor due to it history, prejudices etc., Even after presenting and projecting (even if we assume with ulterior motive) Buddha as 9th Avatara of Hinduism, current Dalit-Buddhist movement doesn't see itself as part of overall Hindu structure or want it to be that way. For crying out loud, these Dalit-Buddhist leadership cry that Hindu Grama-Devatas are a Brahminic ploy to somehow insult them. The Dalit-Buddhist identity is nothing but a EJ ploy to segregate and separate Dalit-Hindu sections who are wary of Abrahamic memes by giving them a Buddhist socio-political identity.
So if Dalit Neo-Buddhists do not see themselves as part of overall Hindu structure, isn't it better to do something about it and change it. Why this reflexive urge to break ranks with the other! This is the same reflexive response as with not wishing to doing Shuddhi of others because of their "betrayal", or not accepting women back into the fold who have lost their "honor". This is rubbish! If they are some Neo-Buddhists who follow Western directives, then all the better to smuggle in some of our own who fall upon those who seek conflict with Hindus and who are willing to rip apart this mischief-makers. This is a turf of competition, so our impulse should not be one of walking away from it.