Yep, that dreaded 'cannot get' localhost 3000

I thought the culprit was browser-sync or Windows 10 not reading single quotes or environmental variables. I checked the syntax. Seems fine. It runs in node, compiles and apparently performs all the .tasks that I ask of it. But keeps going to the cannot get page. 'Live Server' in VS.Code finds the index.html and displays it fine.

var gulp = require('gulp')
var browserSync = require('browser-sync').create()
var sass = require('gulp-sass')

gulp.task('compile-sass', function() {
    return gulp.src(['node_modules/bootstrap/scss/bootstrap.scss', 
'src/scss/*.scss'])
    .pipe(sass())
    .pipe(gulp.dest('src/css'))
    .pipe(browserSync.stream())
})

gulp.task('move-js', function() {
    return gulp.src(['node_modules/bootstrap/dist/js/bootstrap.min.js', 
'node_modules/jquery/dist/jquery/jquery.min.js'])
    .pipe(gulp.dest('src/js'))
    .pipe(browserSync.stream())
})


gulp.task('launch-browser', ['compile-sass'], function() {
    browserSync.init({
        server: "./src"
})
    gulp.watch(['node_modules/bootstrap/scss/bootstrap.scss', 
   'src/scss/*.scss'],['compile-sass'])
    gulp.watch("src/*.html").on('change', browserSync.reload)
})

gulp.task('default', ['move-js', 'launch-browser'])

...I've changed 'launch-browser' to 'server', I've rewrote using 'const' instead of 'var'. Any point in the right direction would be just great. I've read and tried all other posts here. All to the same end.