Aside from the other comments responding to you with relevant counter-points, a discussion over increasing a gig economy's footprint should account for Coase's Theorem (already mentioned by one other comment elsewhere in this thread, and I'm surprised more people aren't bringing it up) that points out the transactional costs of being your own contractor. The logistical tail that US contractors deal with gets non-trivial very quickly, especially as you climb up the value ladder. Entry is very easy and the logistical tail there is tolerable, but stay at that entry level and you never gain appreciable negotiating leverage. US healthcare is a huge elephant in the room, as Buffett recently pointed out earlier this year.
What we call "gig economy" are p2p transactions in name only in our existing incarnations of them: most of these are oligopolistic markets dominated by only 2-3 major "platforms". They are not a free market with lots of choices the giggers choose from with low to no switching costs; if there was an equities-exchange-like platform that did the matching, with equities-exchange-like margins, and many such platforms, that would be closer to a free market, and even smaller margins under a utility-infrastructure model of the platform where the data is open formats while the platforms compete on service and process would be even more free. Their cut of the action to facilitate the p2p transaction is not a fraction of a percent to 1-2% like highly-contested free markets are (like retail groceries). After that big cut, their "contractors" are still saddled with most of the transactional costs of being a contractor like various forms of business insurance, health insurance, accounting, payroll compliance, regulatory compliance, etc.
Our entire asset valuation pyramids and the dominant economic paradigm are built upon an assumption fairly stable income streams at the bottom, not to speak of the meta-assumption of constant growth. Insurance and credit banking are the big areas, but these assumptions are interwoven at a very fine-grained level throughout our civilization. A majority or even plurality economy based upon gigs transitioning from our current model is necessarily going to go through a drastically lower asset valuation period, and with oligopolistic platform choices depressing negotiation power on the supplier/contractor side, that period could extend indefinitely. This isn't per se "bad", or "good", but advocating the gig economy should come with realistic and frank discussions of side effects management.
People respond to incentives. The core incentives in a gig economy are: you cannot predict when your next check will come, you cannot even predict how big it will be when it comes, nor can you feasibly control the terms under which it comes. The pullback in consumption and spending from current levels will reflect people's response to those incentives. People's lives will be patterned after long-time survivors of this type of economy; certain subset industries in movie and TV entertainment have been structured this way nearly since inception for most participants, for example. General rule of thumb is you live way below your means, and you spend at most 20-30% of your high water mark annual earnings over a 10 year running average. Income swings of 100% or more over 2-3 years are not uncommon.
Under a gig economy, you will wait until you hold 20-50% down payment before committing to a mortgage; many people's annual incomes are so wildly inconsistent they can't get a mortgage, period. Note that the US new mortgage originations market currently relies upon around 3.5-5.0% down payments; the traditional 20% is now rare, the average is 11% (in the <35 year old cohort, it is 8%). One estimate at requiring 20% down payment is a 30% reduction in mortgage originations [1].
I speak to all this from spending the vast majority of my adult life as an independent business entity in the US, by choice (most years I have one client ask if I would ever consider going perm at reasonable compensation levels). My position harbors no animosity towards the gig economy; indeed, I'm an active participant in it and biased towards it (for various reasons). But realistically, it is not for everyone, and not even for the majority or plurality; it is a sustainable enough model for only a very small part of what we are evolving our current system towards, unless we put severely eroding current asset valuations onto the table, whether for 10 years (my minimum estimate) or indefinitely.
The key factor to keep an eye upon IMHO is whether or not the proposed change represents a shift towards a more symmetric power dynamic between participants. Right now, corporate structures wield asymmetrically more power than individuals, and a gig economy does not change that in most contexts, and worsens it in many other contexts.
[1] https://blogs.stthomas.edu/realestate/2011/05/16/revitalizin...