They can have all the money in the world and it doesn't mean much in this context.
For while Microsoft is going to invest heavily in a Cursor / Windsurf like product and likely do alot to ship it in their editors - likely with exclusions or lag times between updates on other platforms - there's zero reason for Google to do this for example, when they could sell through Gemini for Code as an extension across all editors.
I don't see JetBrains having issues because of AI tooling, for most of these companies, its a boon to be on the JetBrains platform. Especially because JetBrains has lots of enterprise customers who would naturally be very interested in buying AI tooling for their developers. Its a natural market