Learning programming requires a lot of perseverance and will power, one of the biggest challenges about learning code is to keep going and stay motivated. Seeing results and building stuff that is useful is a great motivator, Python can make that happen quickly.
Not saying it's for everyone, if the low level stuff gets you excited obviously go for it.
My point is; we all learn very differently, and for a lot of people Python is a great choice as first language because it's high level, and because you can get to results fairly quickly.
Just like you say it will be easier to learn Python later, the reverse is also true. Your first language is always the hardest, the second one, whatever it is, will be much easier.
You hear this "learn the fundamentals first" so many times and it really bothers me as I don't think it's great advice, I think for many people it's not a great way to learn. I know it isn't for me.
My suggestion is to learn in a way that works for you. Getting to results quickly, to only later really learn and understand the things you did is a great method. I know it worked for me, and I know it worked for quite a few people who I helped learn to code.