I think so, but there's always something to be desired.
To give a typical example, Mr. Shen Peng, the former chairman of the Chinese Calligraphy Association, once bluntly admitted that he never came to the post and rarely studied regular script. But isn't his cursive writing very good?
Looking back at the selection of many people who have been vice chairmen of the Chinese Calligraphy Association, the regular script they show is really not good, which fully shows that people who do not have a foundation in regular script can still learn cursive, and they are also very popular! Otherwise....
Then again, there is a difference between having a regular script foundation and not having a regular script foundation. Just as a painter has a sketching foundation and does not have a sketching foundation, his painting foundation will not be solid, otherwise the three-dimensional relationship, the relationship between light and shade, the relationship between space and structure, will bring shortcomings in the interpretation and expression of his future works.
Looking back at some of these masters who are inferior in regular script, although the cursive writing is sky-skimming, carefully taste some "congenital deficiencies", and there is a phenomenon of "looking like a god, vacancy in the middle", friends with a little calligraphy skills, from which we can see the advantages and disadvantages of high and low, and the fly in the ointment. Of course, the momentum of this group of people is not bad, and it is true that they speak the bold words of "surpassing the ancients", but they can't block the emptiness of their skills between the lines!
Okay, digression, in a word: why not do it if you have a regular script foundation.