They are excited to play the next campaign with you at the helm - you have succeeded.
RPGs are about fun. It's in the name. Game. I can't imagine a scenario where nobody had fun and wanted to commit to another adventure with you. In this respect, you have been a successful DM. Given these things, you definitely shouldn't be so hard on yourself. A good DM is the one who effectively fosters a fun environment at the table. If you achieve this while completely railroading everything, that's great! Some people prefer that style of play - the only right way to play a game is the fun way. You said it yourself, "they don't really care that I do this". I understand this to mean something more like, "they are perfectly okay with my style of running the game", after all, they're excited for another go at it.
The DM gets to have fun too.
If you're not having fun, then this is where you need to focus in. Why aren't you having fun?
If you're not having fun because you feel that you are bad at DMing, the evidence seems to say otherwise. Having fun for you may just look like recognizing that your players enjoy what you are doing at the table.
But maybe you really just aren't having fun DMing. Maybe recognizing the fun your players are having isn't enough to make it fun for you. This is okay too. It is okay to no longer have fun doing something. DM burnout is a real thing. Maybe you just need a break. If this is the case, talk to your players about it. Tell them you need a break from being the DM. Remember - you don't owe them your DM services. It is okay to say no to another campaign.
It sounds like your players are having a great time, and this is the most important feature of a good DM. If recognizing this is all it takes to encourage you back into the DM seat and have fun yourself, all the better. But it's also okay to put your own fun first, and figuring this out may require some self-examination and communication with your players.
Openly communicate with your players about how you can improve.
My DM and I do this after nearly every session. A few days after each session, we go over the last session. I ask things such as, "How could I improve as a player over this last session? What were some things you liked and disliked about how I played my character" Likewise, my DM asks similar questions, and we give each other honest feedback.
I can remember one session where my DM felt it was a particularly terrible session. He was very hard on himself and felt like he totally failed us. It also happened to be one of my favorites, and unanimously praised as one of our funnest games by the rest of our party. But you never know unless you have this conversation.
Approach your players and ask, "What did you guys think of the campaign? Are there any things about my style of DMing you think I should work on and improve?" Their answers might surprise you.
Perhaps it's someone else's turn to DM
Alternatively, if you really don't want to DM again (which is okay), approach your players and say something like, "Hey friends, I'm really not feeling up to running another campaign right now." Again, it is important that you are having fun as well, and being honest with them is better than silently dreading every session as you prepare.
This question may also have some helpful perspective: How can a GM prevent growing disillusioned with their own game?