It all depends on definitions.
There are slight differences in the way some things work. There's also an excellent ability to assign keys to macros and shortcuts (so you can, if you wish, match Word). You can also quickly set up key functions either specific to Libre Office Writer or to the whole suite together. I haven't used it for ages, but Libre Office Writer seems much easier than when I last did use Word. And I'm paying nothing to Microsoft, and I'm not required to use a web browser or link to internet (office 365, etc.).
The only downside is that outline numbering is awkward, but then it is also in Word anyway (and was notoriously broken/crash-inducing for years if not a decade). Greybeards will remember how good WordPerfect was at this sort of thing (and indexing, ToC, etc.). Libre Writer does ToC very well, and Word has probably been fixed by now, but I can make all that stuff work for me, so I'm not bothered by any differences. I use styles a lot (I like structured documents), and those are good and easy to use.
There are a few, mainly display/party tricks in Excel that aren't in Libre Office Calc, but for those I use Google Sheets. For example, you can fake Gantt charts in Google Sheets (using "Sparklines"), and it's hard or impossible in Libre Calc. But even in that case there's also an Open Source project planner that'll do them, it's a bit limited (e.g. no resource levelling), but free is a _lot_ cheaper than MS Project nowadays!
