PowerPoint rendered the images in the ODP poorly, like it jacked the contrast up to 100. Saving the document as a PPTX within LibreOffice and then playing it on PowerPoint fixed the issue. From my naive perspective MS Office seems to have issues with ODF just like LibreOffice has with docx/pptx/xlsx/etc.
But if you can't absolutely rely on it to be totally compatible, then it's a total non-starter. Not worth the risk.
Counterpoint: Google Docs. Its OOXML compatibility is for shit. Its adoption is HUGE.
Not one person mentions how amazingly shit its OOXML compatibility is, even for quite simple DOCX.
Almost nobody in an office uses the fancy bits of Excel. Spreadsheets are mostly used as flat-file data stores.
And Office is notoriously incompatible between different versions of itself.
In practice, I don't think the file compatibility objection to LibreOffice is real. It's just an excuse.
The actual competition is Google Docs, which is a shitty word processor and a shitty spreadsheet and a shitty presentation app, but absolutely brilliant at quick and convenient collaboration. That's why LibreOffice is working super-hard on the web-based online version.
This has never been my experience. Even if there's a more robust DB based system, someone will do everything in Excel.