Qualcomm and Huawei are both "fabless" semiconductor companies, like NVidia or AMD. These companies design chips, but do not own foundries to manufacture them. TSMC is a "pure-play foundry", a company that does not design chips, but only manufactures chips that other companies have designed. TSMC is the largest and most advanced foundry.

Huawei (a Chinese company) and Qualcomm (a US company) both design modems[1]. Huawei and Qualcomm both need TSMC's fabs, or else they will not be able to manufacture their most advanced designs. If Huawei can't buy from TSMC, then new Huawei modems will have to be manufactured with inferior or more expensive alternatives.

With Huawei chips now more expensive or less performant, products designed by Qualcomm will be better in comparison. Presumably, this will cause Qualcomm's stock to rise in value, although it may be a net negative for the worldwide economy.

See also the recent announcement that TSMC reached an agreement with the US government to move some of its production to Arizona [2].

[1] Huawei's Kirin/Balong chips directly compete with Qualcomm's Snapdragon chips: both are currently manufactured on TSMC's 7nm process.

[2] https://news.ycombinator.com/item?id=23187698

Huawei is a competitor in the mobile SoC field.

Huawei is one of their largest competitors in terms of 5G chipsets. Restrictions on Huawei would also likely help US companies like Apple, so this move would be a net positive.