French hasn’t evolved/changed much because the académie française was set up in 1635 to “protect” the French language and so stop it from changing 
But it has changed in many ways, almost nobody uses nous in spoken French (apart from stilted/proper/speeches). And l’académie française will never be able to control street language so it does change albeit very slowly compared to other languages.
Let’s not forget that crappy inclusive writing system they tried forcing on everyone and which some universities and public institutions take delight in writing to you in.
And is the cause, or at least reason for, all the faux amis set to confuse us. I could save myself so much time when writing rapidly in French if I didn’t have to keep checking that I wasn’t falling foul of one of those, as well as double checking gender (which matters more when writing) only to find that I was right all along. 
Yes, that’s what I watched immediately after your original link. It explains that English had genders many centuries ago, but not why, alone amongst most others, it changed. @vero came up with the best explanation.
I seem to have missed this conversation
I knew the rules in question - though I must confess I had not made the mental leap from guêpe to wasp.
Amazing how one root can give rise to two completely different words.
There’s a famous old story of interest to linguists about how words cause trouble, in mediaeval Kent some people ended up murdering some other people (from actually not very far away thinking they were marauding foreigners) who came to buy eggs - the people said eyren instead of egges or vice versa and that obv made them dodgy and suspicious and to be killed. Shades of sibboleth/shibboleth down at the stream.
Gu and w are the same, circumflex accent indicates missing S hey presto same word. Avispa in Latin and Wespe in German. Welfs and Guelphs, Ghibellines and Ibellines même combat.
Languages are such fun!
Really? How about squelette théorème beauté and those nice words that are masculine when singular and feminine when plural (they were mentioned a shortish while ago).
English isn’t the only one. Other genderless languages include Armenian, Georgian, Hungarian, Finnish, Estonian, Turkish, Chinese, Japanese, Korean and Vietnamese 
I am really pleased at that, don’t feel so lonely now. 
Also, the next time I ask a French person why gender and get a shrug in return as if it was us that was wierd, I will reel off that list. 
They will say “ça me fait une belle jambe”
Old English actually had three genders, masculine, feminine and neuter, nouns had 8 to 10 different endings. It started to change and simplify after 1066 becoming middle english in about 1150.
Village signs in Occitanie are in French and Occitan, but obviously lack pronounciation guides in either language.
However, if I’m speaking to someone local, I don’t use either the Occtian version nor the French version of our village’s name, but something that must have evolved from the former but not quite reached the latter. In French the village is La Roque/ Laroque Bouillac, whereas in Occitan it’s usually La Roca Bouhaca, but for locals it’s Laroque Bouillac, with both final syllables pronounced unusually hard and emphatic.
When we first came here and would give our address to people, they’d do that funny screwed-up, twisted French mouth thing that indicates they can’t recognise your French words. However, when we started using the local hybridised pronouncition everything became fine. Similarly, on local markets, there are some stalls where I now emphasise the final ‘e’ so that cinquante, becomunaa much harder chinquanté. Love it! Just like Cumbria - well, sort of…
Thoughtfully tailoring one’s language to one’s audience is generally a good rule of thumb, but shouldn’t be conflated with the dog whistle faux populist utterances of Sunak and Truss.
I think gender is unique to European languages. Am I right?
For sure European languages have very complicated grammar with word endings always changing.
Only some are, most around here are not.
No. All sorts of interesting things including gender and number and classes of things occur in all sorts of other languages.
Some do, some don’t, if you mean according to if it is eg a noun and if it is subject, direct object, indirect object etc. It is called inflection if you want to look it up.
Example Mary (subject) sent a letter (direct object) to George (indirect object) English does it with word order and prepositions, languages like Latin or German do it with endings which vary. You could argue the case (boom boom) for either way. Some languages do it in a much much MUCH more complicated way. That’s what makes languages fascinating and fun
But the languages you mention (English, German and Latin) are all European languages.
I speak some Asian languages a bit (Thai and Indonesian), almost no grammar, very easy, a word is a word, it never changes it’s form or ending like in all European languages.
And no genders!
Arabic has gender for things like numbers which alter in agreement depending on the size of the number, weirdly. Similar things happen in other languages. Bahasa is lovely and simple.