Ngram viewer results for "Buddhismus" from German
from 1800. There is a major spike at 1928 with a leveling off afterwards punctuated with some lesser peaks, 1948/50, 1963, 2001.
WOW! Taking the German graph back to 1600 there is a spike around 1780!
People in the West could have known something about Buddhism even in the late 18th century!
So really Westerns have been calling the lamas from afar for 232 years or so.
for Buddhism for American English show constant growth from 1820 with a decline
initially around 1800.
The results for Buddhism for British English show constant growth from 1820.
The results for Dalai Lama
in American English from 1700 to present show some activity just before 1800, activity through the 19th century with a at peak around 1903 (so around the time the 13th Dalai Lama fled Tibet) and a graph with a step incline from 1980.
The results for Dalai Lama in British English from 1700 show more blocky waves but also show activity from 1750 or so with a more recent decline.
The results for Kalachakra in American, British ENglish, German and French are amazing. All show a significant spike from around 1980 but American English and German shows some activity around 1900 and 1890 respectively.Kalachakra
Ngram results from 1700
Medicine Buddha also shows measurable activity from the 1960's in American and British English although with British English the result is a spike in the 70's a drop to nothing and then slight growth. In American English it is a curve with a steep slope from 1960 (probably because the Brits have health care and thus don't need Medicine Buddha and in the US we have no health care
).Medicine Buddha results
From a perspective outside Mahayana Buddhism, many people would say that Medicine Buddha is pretty obscure. Nonetheless the bigram actually measurably appears in English.
Also the Ngram viewer is case sensitive and shows slightly different graphs for lower case buddhism.
The result for Tibet
in British English is fascinating with measurable references beginning just after 1650, then a drop to nothing, then from around 1740 a constant, albeit spiky, growth with a recent drop.
In German sources the graph is more spiky but there is constant reference from 1765 or so!tantra
shows up in the mid-late 19th century in German and American English but in British English there is a huge spike around 1670 with references from around the 1750 (this makes me think that there might be a dialectical usage of an obscure British homograph - however sutra
has the same 1670 spike so probably not).
Similarly budismo, sutra, and tantra all appear beginning in the early 1800's in Spanish with massive growth in the 20th century ending with a graph with a steep slope in the 2000's.
The graph for Buddha ( 佛 ) in Simplified Chinese
shows blocky waves but a massive spike around 1835, two peaks in the 20th Century around 1915 and 1938 with a decline after 1950.
Overall I'm not seeing the decline that you posit.