I don't think that's remotely true if you keep the responsive web app simple. YNGNI and KISS and what not.
I've been doing this for over ten years. In that time I've seen large web applications built for under 4k; I've also seen massively overbuilt simple applications go for 50k+. It comes down to often how needlessly complex you make the stack.
If you stick with solid simple guaranteed tech instead of cutting edge you can knock a web app out relatively cheap and easy.
When it comes right down to it, 95% of web apps have two jobs. Present text to the user, take text from the user. Everything else is a nice to have. HTTP has been doing those two jobs amazingly well for decades. It's a solved problem, don't make it harder than it needs to be.
Lastly: Don't fight the browser. Design for the browser. Responsive is easy if you design for things to flow as the browser would have it. It's one of the biggest mistake I see so often. If a design requires you to fight the native behaviours of the browser, it's likely a bad design. Fight back against that junk, it just makes future work that much harder.
tl;dr Develop for the web of a couple years ago and not the web of today. It'll save you time and headaches.
I've been doing this for over ten years. In that time I've seen large web applications built for under 4k; I've also seen massively overbuilt simple applications go for 50k+. It comes down to often how needlessly complex you make the stack.
If you stick with solid simple guaranteed tech instead of cutting edge you can knock a web app out relatively cheap and easy.
When it comes right down to it, 95% of web apps have two jobs. Present text to the user, take text from the user. Everything else is a nice to have. HTTP has been doing those two jobs amazingly well for decades. It's a solved problem, don't make it harder than it needs to be.
Lastly: Don't fight the browser. Design for the browser. Responsive is easy if you design for things to flow as the browser would have it. It's one of the biggest mistake I see so often. If a design requires you to fight the native behaviours of the browser, it's likely a bad design. Fight back against that junk, it just makes future work that much harder.
tl;dr Develop for the web of a couple years ago and not the web of today. It'll save you time and headaches.