It's a good question.

I'd bet it's less to do with the journalists than with the editors / owners.

Don't know who you have in mind. But British BBC:

Feb 2022 "How hard will it be to defend Ukraine from Russian invasion?"

December 2023. "Ukraine will... strengthen its defences"

April 2024 - "Ukraine has been defending itself against Russia's full-scale invasion for two years"

Same reason why journalists and politicians avoid using the word occupation when talking about Israel and Palestine. Interests or ideology

Because the media outlets are owned by corpofash

We don't know what an eventual outcome will be right now and it would be... weird to talk about help financing "defense" for years and then actually negotiate for concessions.

It's an open secret that if all Russian nukes would disappear over night, the other members of the UN security council would probably party for a week. The US (and the EU) is supporting Ukraine because that's the right thing to do AND it is in their interest because who knows what a bigger Russia will do next. But they're also doing it because it's weakening Russia and that's also in their interest, even though they would never publicly say it or not with the intensity that they actually think that way.

Long story short, if the absolute optimal (for Ukraine and "the west") thing happens:

• the war exhausts Russia more than Ukraine + supporters
• the timing for negotiations is chosen in a way that is extremely bad for Russia, to the effect that Russia doesn't have to just apologize, return territory, pay reparations, and all that, but ALSO give up other things.
• like UN observers and limits to their military.
• nuclear disarmament
• ???

It would look extremely badly if politicians, actual leaders of nations, were to talk about "defense" for years and then actually ask those things in the end. Which they want to.

So (imo, it's all speculation) it's preemptive PR management that leaves room for that asking for more things than would be justifiable with "defense".

It also makes sense for good, honest journalists to use this language. Because they're trying to be neutral and leaving the opinion forming up to the reader, as far as they can. They want to let the facts speak for themselves. Even if they're pro Ukraine, they want the facts to convince you to be pro Ukraine, not their phrasing.

So, regardless of whether they're rage baiting, paid off by Russia, or trying to do honest journalists, it always makes more sense to use neutral language rather than having a pro Ukraine bias.

cuz "defenfing", by todays standards, means killing innocent civilians (mostly children), and is therefore already reserved for Israel.