hmphotographic

Okay, but that needs fixed.

Another web design agency here echoing all previous comments on this thread and others.   Being able to manage media is a must have feature.  

I agree! Huge fail!

Also, the option to add multiple images and to add to a gallery section. At the moment you can only ass 1 photo at the time.
Second, the option to change  the file name (alt text) to improve  SEO. at the moment you can only change  the description of the image, not the file name. This is super important for SEO optimisation.
I hope you will add this to your update 

Couldn't agree more, it's ludicrous that in 2021 you can't manage or download your files. Total joke!
Please @Squarespace Guru help! 

Dear Squarespace Developement Team,
For the love of all things web design - PLEASE rectify the image/media file management for BOTH designers who help SELL your service and for those who manage their own sites.  We have other options and while I have helped sell to and set up small business websites via Squarespace - this past week I was in a situation where I could have really leveraged Squarespace to a room of emerging artist learning how to build their own websites, and because image/media file management is SO crucial and can be a HUGE time suck to contend with - preventing artist from making art because they are wasting precious hours trying to organize their web presence - I DID NOT recommend Squarespace. Instead, WixPix became the recommended website host to about 1,500 students in this business course... They have a file management system on the backend of their platform... The fact this has not been addressed in my time as a customer baffles me. There are a lot of important devevlopments and very grateful for the ones made around eCommerce, but even for eCommerce image file management is CRUCIAL. It's literally dreadful when a client needs a 100+ product images updated and REQUIRE somehow removing the outdated images so they don't confuse the customer.
This should be addressed, must be a top level feature, and if you don't have the people on your team capable of making it possible - hire someone who can.
Thank you.

I can't believe this is not a feature. I accidentally uploaded a non-relevant screenshot (when selecting multiple images for a gallery) , that I absolutely don't want my clients to have in the library of their shiny new website and cannot believe that the only way of not handing over this random image (along with all the wrongly sized test images I used along the way) is to start a whole new website. How has this not been solved yet? 

Still following this.....with SO many people requesting this, why is this not a feature yet? This is a big deal breaker for us as well when we create a custom site and duplicate to work on for a new site, we do NOT want old imagery stored and transferred. 
I am baffled that something like changing the tear-dropper icon to that annoying new plus symbol add feature would take priority over something like this where SO many people have voiced their frustrations. I have yet to run across threads where people were complaining about the old teardrop insert feature so why make that a priority when you have real users here voicing concerns? 
And while we are here recommending features, why not simply offer a BLANK canvas with absolutely nothing saved so we can start from scratch instead of having to delete or replace imagery. For so many of us creating more custom sites, it is frustrating to have to do this where as a totally blank canvas would be incredible and something we have been asking for for a long time now!

Yes, but when you upload a lot of test images, or have different sizes or versions of an image, this becomes a huge amount of images in the search gallery. You have to wade through all of them, and can't delete them.