The simplest way to easily make SumIFS-like functions in my opinion is to combine the FILTER and SUM function.
SUM(FILTER(sourceArray, arrayCondition_1, arrayCondition_2, ..., arrayCondition_30))
For example:
SUM(FILTER(A1:A10;A1:A10>5;B1:B10=1)
Explanation: the FILTER() filters the rows in A1:A10 where A1:A10 > 5 and B1:B10 = 1. Then SUM() sums the values of those cells.
This approach is very flexible and easily allows for making COUNTIFS() functions for example as well (just use COUNT() instead of SUM()).