First of, a little bit of clarification is required due to Canadian law and how it differentiates between intelligence and evidence.

Link 1

Link 2

Even though, a long and complex read, I urge you to go through these two links at least without going into depth the Canadian law, regarding what can be represented and what cannot be represented as evidence.

Starting from the hijacked Air India flight, and then multiple domestic cases in Canada (police intelligence versus what evidence can the police bring) and a couple cases of Chinese interference in Canada's law and order (actions such as setting up of local CCP police stations whose job was to force Chinese-Canadian citizens, permanent residents and naturalized Canadian citizens of Chinese descent through harm to their family in China) have set precedents in Canada.

Now,

Based on this, let's take an example.

Intelligence: Indian Ambassador talked to the accused. Yes, sure they talked. Maybe they had a problem with their OCI or NRI cards and needed immediate high level intervention.

Evidence: Indian Ambassador talked to the accused. Canadian authorities illegally obtained recordings of the call and thus, cannot present it as evidence, as that would basically be an intelligence suicide.

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The above is an example. I don't know the truth.

What the Indian MEA is saying that Canada has only presented the first, and not the latter. When accusing a diplomat of being involved in assassinations (even Pakistan, which has had several incidents of unknown persons killing India's enemies, has accused India's spy agencies, not the Indian Ambassador in Pakistan) you better be sure that you provide the latter, and not the former as it accuses the primary representative of India in Canada, as being an extension of assassins.

This is unusual, as the intelligence chief posted is not the ambassador to the host country, rather a separate posting. In case of friendly nations, a host country requests an intelligence chief to spy on its own citizens, because the host country is usually forbidden by law to blanket spy on their own, while a friendly country can, just as a part of their own intelligence operations.

Accusing a posted Ambassador of a large, democratic nation, which isn't a complete failure and has a strong rule of law, is a BIG deal. Usually such accusations aren't done, without concrete evidence, and declaring Ambassador's as persona non-grata without the Ambassador themselves doing something like killing someone in accident or promoting corruption etc. in the host country is something not large mature nations with well developed diplomatic machinerys do.

Canada insists that handing over intelligence was sufficient due to the strength of the intelligence handed over and India should obtain evidence after it's own internal investigations - which I find ironic and a huge blow to Canada's diplomatic maturity.

I say, Canadian diplomacy is mature, because Canada has a diplomatic presence in Cuba, which is sanctioned by America and American and Canadian diplomacy should go hand-in-hand, seeing the unprotected border between the two, and the total trade between the two (almost annually, a trillion dollar trade).

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On the surface and even after a bit of deeper dive into this, it seems more and more that Canadian PM used this opportunity not as the representative of the Canadian people, but as the party member of the Liberal Party of Canada (LPC), intertwining Canadian diplomacy which is external facing, with Canadian politics, which is internal facing and US facing.

I don't know how this will play out, either for Canada or for India - but unlike Canada where Pierre Poilievre basically said JT fucked up big time, Indian political scenario looks much more united.

(A lot of Canadian millet/pulses are India's biggest food imports, where India itself doesn't make enough to meet its own demand. Those farming regions could get devastated by Indian action on Canadian pulse imports, which are rural and conservative party leaning, so take PPs statement with a pinch of salt). Major pulse growing provinces of Alberta, Manitoba, Saskatchewan are conservative heavy provinces.