This image example on this page is 1000px in width and is only 104k in size. The quality is more than acceptable for web.
This was exported from photoshop on 40% quality and is more than a 300% reduction in file size from the original image.
Please resize your images accordingly. This is good practice, and also good consideration to each other as you're all on a shared server.
Image > Image Size...
Firstly make sure you image is an appropriate size in terms of dimensions. 1000px is still large, if it doesn't need to be that big, then it shouldn't be.
File > Export > Export As...
Drop the quality right down (50% and below). Keep going until you notice some real degradation in the image. In the example above 50% was still over 600k, but 40% quality took it down to 104k. That's a trade off that's well worth it.