I have multiple banks, tangerine is one of them but gave the least issues. I don't think the issues were always on the bank's side though because every time I had sync issues i'd open up a support chat, they would do a "forced refresh" on my account and it would be fine. If it was an issue with the banks making changes to their systems I don't think it would be that simple.

A huge issue I had since day one is none of my transactions get the transaction rules applied to them, so any benefit/time savings of automation are eliminated. I have identified the issue multiple times with their support team, it is caused by my credit cards also including the cash back rewards in the merchant name, so they are never the same. This would easily be fixed on their end by not requiring a perfect match, using wildcards or regular expressions instead, I waited over 2 years for a fix and still nothing after talking to them at least 8 - 9 times on the matter.