That's opinion really.
That said, you should consider that after a text's string has changed, you may want to re-evaluate its position.
If your text is 'anchored' to the top left, changing its position is likely unnecessary. And, in fact, changing it could make it jump around a bit.
If you text is anchored elsewhere - such as the centre - adjusting its position is very likely required. For example, if it start at 3 characters and is centred but then changes to 30 characters, it will no longer be centred and its 2nd character (approximately) will still be in centre of where the centre of the text should be.
It's worth noting, though, that baselines and maximum heights can change depending on the characters used in the text so for a "centred text line", you may wish to only adjust the x position and leave the y position in what you consider correct.
For example, imagine centring "aaayyy" and then changing it "aaaAAA" and centring that. It would be quite noticeable that the 3 lower case as have their vertical position move.
tl:dr;Yes, if you're centring text, adjust its position every time you change its string.