It's diplomacy though. Some things are better said behind closed doors as it were.

Going back to Cold War brinksmanship, the point of NATO was to loudly say that you were ride-or-die, go-to-the-wall with all your NATO homies. It made the risk of messing with NATO countries too high, likewise with the Warsaw Pact.

Now would all NATO allies go all in? 100%, all the way? Who can say with certainty. Still, so far there's only been one US president who has said… it depends. For the record, Trump walked that back, but it certainly got a lot of NATO countries closer to Russia to quickly point out that they were over the NATO 2% GDP commitment.

Still, Article 5 has been invoked once in NATO's history, and it was by the US. It's why Canada was in Kandahar, Netherlands in Helmand, etc. Too my recollection, every single NATO country participated in Afghanistan at the US's request.

Also, every NATO country on the frontier (as it were) is well over the NATO 2% GDP minimum. The three Baltic countries, Poland, the UK and the US have been over the 2% GDP minimum for a while. Finland is already well past that before joining, and I believe several more countries will hit the goal in 2023.