Xi's undiplomatic behavior and his accusation that Trudeau "leaked" the joint conversation to the media lack any basis since the alleged "leak" was a standard readout from the PM's office. Moreover, why should Trudeau feel obligated to maintain secrecy when China is likely interfering in Canada's elections? If Trudeau can be accused of anything, it's of being too soft on Beijing.
Given the West's characteristic disrespect displayed by Trudeau's indiscretion, Xi's anger is not surprising. Add to this the fact that China is being accused by Canada — a junior partner of the US — of interfering in the 2019 elections without presenting evidence. Beijing would like to see fruitful dialogue and good bilateral relations with Canada, but these must be based on mutual respect.