A PhD journey is bounded in many ways.
You can only read a finite number of papers and articles to build up your knowledge.
There’s a cap on the number of words that a thesis can reasonably contain.
You have only so many productive hours in any working day and pushing beyond that will not bring greater progress.
And you have hundreds of days to do the work but those days will eventually come to an end – and then you’ll have weeks to prepare for your viva.
Consider your limits as you start to get ready for submission and your viva. What do they show you?
Perhaps there were other things you could have done, but if you’re a typical PhD candidate those limits will show that you are knowledgeable. You embraced your work and studied. The limits of your PhD journey will demonstrate that you worked hard enough to get things done. You’ll have a thesis with thousands and thousands of words as proof that you stayed determined.
There are limits that come in many forms, but none detract from the picture presented of you and your work. You did something. You made something that wasn’t there before and you can be proud of what you’ve made.