[1] https://gizmodo.com/im-buying-an-iphone-because-im-ashamed-o...
edit: Ok this obviously isn't black and white, but I'm saying this should be considered among other things.
For the most part class signaling on the easier end (looks, mostly) has more to do with choices than outright spending. It's why a relatively poor college professor on the East coast can still look "upper middle". Their clothes may be a bit worn, some hand-me-downs, some thrifted, but they're the right clothes. Swapping the legible t-shirt & hoodie for a cotton button-up and wool cardigan or a blazer and the $100-150 sneakers for $100-150 (clearance, seconds, or used) leather loafers will do a lot more to signal higher class than an iPhone, and none of those clothes need look new—making the mistake of spending money on stuff like electronics or boldly-branded expensive clothes while getting other things very wrong is a class marker, but not one most would intentionally choose to display if they understood it.
[EDIT] in short, always having new phones and video game consoles and such only signals wealth & higher status to poor people—absent other markers of higher class they'll actual read as low class to everyone else.
Teachers in my children's schools make a point to widen their verbal culture in addition to what they teach. Also (if not mostly) so that they send the right signals (which in France is among others your general culture)
The risk is buying into status symbols of a class beyond your reach. You may signal a certain amount of wealth by buying the latest iPhone, but the "rich and educated" won't be fooled. They will quickly notice where you are living, the car you are driving, the clothes you are wearing and how you spend your vacations, etc... And if it doesn't match, you will get ridiculed. You will be better off living within your means. The rich usually have good finances, that's why they are rich, and they will be more likely to accept you if you have it too.
But getting shunned is not the worst that can happen. If you try to follow them, you are going to get burned very quickly. If they can afford a $100 dinner on a whim, they are going to do it, why wouldn't they. And if you want to stay in their group, you will be tempted to follow, except that you can't afford it.
What's so interesting in the rich (and supposedly educated, I'll take your word for it...) groups that you have to buy into them with expensive junk?
Do you have any idea how many uneducated rich fools there are nowadays and how they spend their wealth in just as stupid ways as the poor, the only difference being that their capital income often actually sustains that foolishness? LVMH's success is a good hint.
The fact that opportunity is driven largely by networks, and that networks are typically class-gated (not exactly wealth-gated; most people recognize that class and temporary circumstances aren't the same thing.)
Unfortunately, social seeking by the poor who aren't mentored on social signalling by someone already in or experienced with higher classes is likely to reflect lower-class misconceptions of higher-class signals, and fail as class signalling.
This is true, but what kind of opportunities are of vital importance for someone who is wealthy already and which of those can't they just buy into without networking? Or, to put it more plainly, you've got a nice house, your kids go to the best schools, your capital income provides you with a comfortable lifestyle, what "opportunities" are you lacking exactly?
The pseudo rich with all the status symbols are generally more in debt than the poor person who needs to use a car title loan to get food at the end of the month!
Of course there are also the "filthy rich" with a ton of money with all the toys just like the pseudo rich. They are a minority of those living that lifestyle though.