In Brazil, we also use commas to separate the units and tenths places.
I don’t remember a single instance where this ambiguity actually caused confusion.
Outside academia, I suppose people rarely need to write lots of pairs of real numbers in decimal notation.
In academia, during my Bachelor’s in Mathematics, except perhaps in physics, experimental physics, numerical calculus and statistics, we were expected to carry out all calculations with full precision. The exercises were designed so that you could solve them by hand, without using calculators or computers. As a result, we almost always used fractions in analytic geometry, linear algebra, multivariable calculus, and so on. The same practice continued throughout my Master’s and Ph.D. in Mathematics. For better or worse, this is often still true today, even for students from other majors taking Calculus, Linear Algebra, and similar courses.
I believe this is, to some extent, a French influence on our undergraduate and graduate education, but I could be wrong.
Of course, if one adopts the convention of writing at least one decimal place to the right of the units digit, the ambiguity disappears completely, even for triples and $n$-uples:
$$
(1,25,6,0),
$$
Integer rarely appeared in experiments/numerical calculus anyway. It is likely we used tables of $x$ and $y$ coordinates separated by vertical lines, instead of pairs of points.
We could just put extra space to separate the numbers from the parentheses and the comma in the middle (and perhaps using slightly enlarged commas)
$$
(\ 1,25 \ \text{,} \ 6 \ ),
$$
$$
(\ 1,25 \ \text{,} \ 6,0 \ ),
$$
or perhaps we use dots instead. Everybody would understand with no issue.