Frontend only devs who know the first thing about efficient queries are exceedingly rare. Solutions like Firebase that do exactly what you are describing are e

Frontend only devs who know the first thing about efficient queries are exceedingly rare. Solutions like Firebase that do exactly what you are describing are extremely expensive and just as limited in terms of functionality, and properly designing security for them is quite difficult. For quite awhile I was on that train until I just couldn't justify the price and limitations, and my frontend stack to deal with those problems became excessively complex.