While reading a scene about some people checking out the luxurious hot tub that is in their building, one of the character remarks:
ご、豪華すぎるほどじゃないが、何とも贅沢極まるというか。。。
which I understand as meaning like: It's not at the level of being too 豪華, but it's extremely 贅沢.
Am I right in understanding that 豪華 is more extravagant that 贅沢?
豪華 in isolation is a positive word meaning luxurious. But if we say 豪華すぎる, it of course turns into a directly negative remark ("overly luxurious" or "too luxurious").
On the other hand, 贅沢 is an ambivalent word that has both positive and negative connotations. When it's negative, it's closer to extravagant or lavish. People often say そんな贅沢なお金の使い方をするな, 贅沢をやめろ, etc. When it's positive, it's almost interchangeable with 豪華.
So the speaker rephrased a clearly negative remark (豪華すぎる) to an ambiguous phrase (贅沢極まる) to make the sentence sound more euphemistic and milder. But if we remove すぎる, 贅沢 is the word that is closer to extravagant.
I think 豪華 and 贅沢 can't be compared by the degree of the expensiveness.
豪華 and 贅沢 means "gorgeousness" and "luxury', but only 贅沢 often includs negative meaning like "too extravagant", "too expensive" and "champagne taste on a beer budget".
I like naruto's answer so I was going to add this as a comment, but it got too long so I am adding as answer. Consider it a really long comment with supplementary information.
When you look at the dictionary (I used kotobank), the definition of 「贅沢」 is to use more money than necessary or is appropriate for one's circumstance, and the definition for 「豪華」 literally included 「贅沢」 in its definition, so there is definitely a lot of overlap in the meaning.
However, one thing that might be useful to know is that in Japan as of now, the word 「贅沢」 no longer necessarily means "luxurious" in the sense that it is expensive. 「安い贅沢」 is very popular these days, here's an example.
You take a paid leave to go off on a 3 day weekend and stay a couple days at a ryokan with outdoor hot springs at an affordable price during off-season. It's not expensive or fancy, but sitting in the outdoor hot springs, enjoying the view, surrounded by the scent of evergreens with birds singing their mating calls while sipping sake is certainly not something you do everyday. This is not 豪華, but it would be considered 贅沢.
So 「贅沢」 is now a word that can be used to describe treating oneself to something, regardless of whether it is too expensive or not. It's more about something nice that's out of the ordinary. On the other hand, 「豪華」 is still a word you use to describe something fancy and expensive. Basically, there is a nuance difference.
Not really related, but with 「贅沢」 you can use it as a verb (贅沢をする) as well as a ～な adjective (贅沢な), while 「豪華」 can be used as a ～な adjective (豪華な) but not as a verb.
