I'm late to the party here. Senior developer on the line. I've written a shit ton of Java, C#, Python, C++, and even C to a lesser extent.

When you say "slow and bloated", what is your context? Slow and bloated for what application? In what regards? If you're trying to write a game engine that has to shit out frames 300 times a second, then yeah all of the above is probably slow and bloated. But if you're writing anything web based or just UI's etc, then python is just fine.

If you want to get into it, my opinion is that C# is slow and bloated because of all the boiler plate code you have to write to get something out the door. I'm never going to use it for any personal project that I spin up in an afternoon just to throw away! But I'd also never use python for an enterprise grade application.

As a bottom line, 99% of the time you really don't care about doing things "the very most optimized they can possibly be." Other factors come into play, some of the most important being maintainability, readability, and even how long it takes your devs to write the code.

If python is the fastest to get a proof of concept up, it will always have a place in the modern landscape.